| 1 | /* |
| 2 | * solo.c: the number-placing puzzle most popularly known as `Sudoku'. |
| 3 | * |
| 4 | * TODO: |
| 5 | * |
| 6 | * - reports from users are that `Trivial'-mode puzzles are still |
| 7 | * rather hard compared to newspapers' easy ones, so some better |
| 8 | * low-end difficulty grading would be nice |
| 9 | * + it's possible that really easy puzzles always have |
| 10 | * _several_ things you can do, so don't make you hunt too |
| 11 | * hard for the one deduction you can currently make |
| 12 | * + it's also possible that easy puzzles require fewer |
| 13 | * cross-eliminations: perhaps there's a higher incidence of |
| 14 | * things you can deduce by looking only at (say) rows, |
| 15 | * rather than things you have to check both rows and columns |
| 16 | * for |
| 17 | * + but really, what I need to do is find some really easy |
| 18 | * puzzles and _play_ them, to see what's actually easy about |
| 19 | * them |
| 20 | * + while I'm revamping this area, filling in the _last_ |
| 21 | * number in a nearly-full row or column should certainly be |
| 22 | * permitted even at the lowest difficulty level. |
| 23 | * + also Owen noticed that `Basic' grids requiring numeric |
| 24 | * elimination are actually very hard, so I wonder if a |
| 25 | * difficulty gradation between that and positional- |
| 26 | * elimination-only might be in order |
| 27 | * + but it's not good to have _too_ many difficulty levels, or |
| 28 | * it'll take too long to randomly generate a given level. |
| 29 | * |
| 30 | * - it might still be nice to do some prioritisation on the |
| 31 | * removal of numbers from the grid |
| 32 | * + one possibility is to try to minimise the maximum number |
| 33 | * of filled squares in any block, which in particular ought |
| 34 | * to enforce never leaving a completely filled block in the |
| 35 | * puzzle as presented. |
| 36 | * |
| 37 | * - alternative interface modes |
| 38 | * + sudoku.com's Windows program has a palette of possible |
| 39 | * entries; you select a palette entry first and then click |
| 40 | * on the square you want it to go in, thus enabling |
| 41 | * mouse-only play. Useful for PDAs! I don't think it's |
| 42 | * actually incompatible with the current highlight-then-type |
| 43 | * approach: you _either_ highlight a palette entry and then |
| 44 | * click, _or_ you highlight a square and then type. At most |
| 45 | * one thing is ever highlighted at a time, so there's no way |
| 46 | * to confuse the two. |
| 47 | * + then again, I don't actually like sudoku.com's interface; |
| 48 | * it's too much like a paint package whereas I prefer to |
| 49 | * think of Solo as a text editor. |
| 50 | * + another PDA-friendly possibility is a drag interface: |
| 51 | * _drag_ numbers from the palette into the grid squares. |
| 52 | * Thought experiments suggest I'd prefer that to the |
| 53 | * sudoku.com approach, but I haven't actually tried it. |
| 54 | */ |
| 55 | |
| 56 | /* |
| 57 | * Solo puzzles need to be square overall (since each row and each |
| 58 | * column must contain one of every digit), but they need not be |
| 59 | * subdivided the same way internally. I am going to adopt a |
| 60 | * convention whereby I _always_ refer to `r' as the number of rows |
| 61 | * of _big_ divisions, and `c' as the number of columns of _big_ |
| 62 | * divisions. Thus, a 2c by 3r puzzle looks something like this: |
| 63 | * |
| 64 | * 4 5 1 | 2 6 3 |
| 65 | * 6 3 2 | 5 4 1 |
| 66 | * ------+------ (Of course, you can't subdivide it the other way |
| 67 | * 1 4 5 | 6 3 2 or you'll get clashes; observe that the 4 in the |
| 68 | * 3 2 6 | 4 1 5 top left would conflict with the 4 in the second |
| 69 | * ------+------ box down on the left-hand side.) |
| 70 | * 5 1 4 | 3 2 6 |
| 71 | * 2 6 3 | 1 5 4 |
| 72 | * |
| 73 | * The need for a strong naming convention should now be clear: |
| 74 | * each small box is two rows of digits by three columns, while the |
| 75 | * overall puzzle has three rows of small boxes by two columns. So |
| 76 | * I will (hopefully) consistently use `r' to denote the number of |
| 77 | * rows _of small boxes_ (here 3), which is also the number of |
| 78 | * columns of digits in each small box; and `c' vice versa (here |
| 79 | * 2). |
| 80 | * |
| 81 | * I'm also going to choose arbitrarily to list c first wherever |
| 82 | * possible: the above is a 2x3 puzzle, not a 3x2 one. |
| 83 | */ |
| 84 | |
| 85 | #include <stdio.h> |
| 86 | #include <stdlib.h> |
| 87 | #include <string.h> |
| 88 | #include <assert.h> |
| 89 | #include <ctype.h> |
| 90 | #include <math.h> |
| 91 | |
| 92 | #ifdef STANDALONE_SOLVER |
| 93 | #include <stdarg.h> |
| 94 | int solver_show_working, solver_recurse_depth; |
| 95 | #endif |
| 96 | |
| 97 | #include "puzzles.h" |
| 98 | |
| 99 | /* |
| 100 | * To save space, I store digits internally as unsigned char. This |
| 101 | * imposes a hard limit of 255 on the order of the puzzle. Since |
| 102 | * even a 5x5 takes unacceptably long to generate, I don't see this |
| 103 | * as a serious limitation unless something _really_ impressive |
| 104 | * happens in computing technology; but here's a typedef anyway for |
| 105 | * general good practice. |
| 106 | */ |
| 107 | typedef unsigned char digit; |
| 108 | #define ORDER_MAX 255 |
| 109 | |
| 110 | #define PREFERRED_TILE_SIZE 48 |
| 111 | #define TILE_SIZE (ds->tilesize) |
| 112 | #define BORDER (TILE_SIZE / 2) |
| 113 | #define GRIDEXTRA max((TILE_SIZE / 32),1) |
| 114 | |
| 115 | #define FLASH_TIME 0.4F |
| 116 | |
| 117 | enum { SYMM_NONE, SYMM_ROT2, SYMM_ROT4, SYMM_REF2, SYMM_REF2D, SYMM_REF4, |
| 118 | SYMM_REF4D, SYMM_REF8 }; |
| 119 | |
| 120 | enum { DIFF_BLOCK, |
| 121 | DIFF_SIMPLE, DIFF_INTERSECT, DIFF_SET, DIFF_EXTREME, DIFF_RECURSIVE, |
| 122 | DIFF_AMBIGUOUS, DIFF_IMPOSSIBLE }; |
| 123 | |
| 124 | enum { DIFF_KSINGLE, DIFF_KMINMAX, DIFF_KSUMS, DIFF_KINTERSECT }; |
| 125 | |
| 126 | enum { |
| 127 | COL_BACKGROUND, |
| 128 | COL_XDIAGONALS, |
| 129 | COL_GRID, |
| 130 | COL_CLUE, |
| 131 | COL_USER, |
| 132 | COL_HIGHLIGHT, |
| 133 | COL_ERROR, |
| 134 | COL_PENCIL, |
| 135 | COL_KILLER, |
| 136 | NCOLOURS |
| 137 | }; |
| 138 | |
| 139 | /* |
| 140 | * To determine all possible ways to reach a given sum by adding two or |
| 141 | * three numbers from 1..9, each of which occurs exactly once in the sum, |
| 142 | * these arrays contain a list of bitmasks for each sum value, where if |
| 143 | * bit N is set, it means that N occurs in the sum. Each list is |
| 144 | * terminated by a zero if it is shorter than the size of the array. |
| 145 | */ |
| 146 | #define MAX_2SUMS 5 |
| 147 | #define MAX_3SUMS 8 |
| 148 | #define MAX_4SUMS 12 |
| 149 | unsigned long sum_bits2[18][MAX_2SUMS]; |
| 150 | unsigned long sum_bits3[25][MAX_3SUMS]; |
| 151 | unsigned long sum_bits4[31][MAX_4SUMS]; |
| 152 | |
| 153 | static int find_sum_bits(unsigned long *array, int idx, int value_left, |
| 154 | int addends_left, int min_addend, |
| 155 | unsigned long bitmask_so_far) |
| 156 | { |
| 157 | int i; |
| 158 | assert(addends_left >= 2); |
| 159 | |
| 160 | for (i = min_addend; i < value_left; i++) { |
| 161 | unsigned long new_bitmask = bitmask_so_far | (1L << i); |
| 162 | assert(bitmask_so_far != new_bitmask); |
| 163 | |
| 164 | if (addends_left == 2) { |
| 165 | int j = value_left - i; |
| 166 | if (j <= i) |
| 167 | break; |
| 168 | if (j > 9) |
| 169 | continue; |
| 170 | array[idx++] = new_bitmask | (1L << j); |
| 171 | } else |
| 172 | idx = find_sum_bits(array, idx, value_left - i, |
| 173 | addends_left - 1, i + 1, |
| 174 | new_bitmask); |
| 175 | } |
| 176 | return idx; |
| 177 | } |
| 178 | |
| 179 | static void precompute_sum_bits(void) |
| 180 | { |
| 181 | int i; |
| 182 | for (i = 3; i < 31; i++) { |
| 183 | int j; |
| 184 | if (i < 18) { |
| 185 | j = find_sum_bits(sum_bits2[i], 0, i, 2, 1, 0); |
| 186 | assert (j <= MAX_2SUMS); |
| 187 | if (j < MAX_2SUMS) |
| 188 | sum_bits2[i][j] = 0; |
| 189 | } |
| 190 | if (i < 25) { |
| 191 | j = find_sum_bits(sum_bits3[i], 0, i, 3, 1, 0); |
| 192 | assert (j <= MAX_3SUMS); |
| 193 | if (j < MAX_3SUMS) |
| 194 | sum_bits3[i][j] = 0; |
| 195 | } |
| 196 | j = find_sum_bits(sum_bits4[i], 0, i, 4, 1, 0); |
| 197 | assert (j <= MAX_4SUMS); |
| 198 | if (j < MAX_4SUMS) |
| 199 | sum_bits4[i][j] = 0; |
| 200 | } |
| 201 | } |
| 202 | |
| 203 | struct game_params { |
| 204 | /* |
| 205 | * For a square puzzle, `c' and `r' indicate the puzzle |
| 206 | * parameters as described above. |
| 207 | * |
| 208 | * A jigsaw-style puzzle is indicated by r==1, in which case c |
| 209 | * can be whatever it likes (there is no constraint on |
| 210 | * compositeness - a 7x7 jigsaw sudoku makes perfect sense). |
| 211 | */ |
| 212 | int c, r, symm, diff, kdiff; |
| 213 | int xtype; /* require all digits in X-diagonals */ |
| 214 | int killer; |
| 215 | }; |
| 216 | |
| 217 | struct block_structure { |
| 218 | int refcount; |
| 219 | |
| 220 | /* |
| 221 | * For text formatting, we do need c and r here. |
| 222 | */ |
| 223 | int c, r, area; |
| 224 | |
| 225 | /* |
| 226 | * For any square index, whichblock[i] gives its block index. |
| 227 | * |
| 228 | * For 0 <= b,i < cr, blocks[b][i] gives the index of the ith |
| 229 | * square in block b. nr_squares[b] gives the number of squares |
| 230 | * in block b (also the number of valid elements in blocks[b]). |
| 231 | * |
| 232 | * blocks_data holds the data pointed to by blocks. |
| 233 | * |
| 234 | * nr_squares may be NULL for block structures where all blocks are |
| 235 | * the same size. |
| 236 | */ |
| 237 | int *whichblock, **blocks, *nr_squares, *blocks_data; |
| 238 | int nr_blocks, max_nr_squares; |
| 239 | |
| 240 | #ifdef STANDALONE_SOLVER |
| 241 | /* |
| 242 | * Textual descriptions of each block. For normal Sudoku these |
| 243 | * are of the form "(1,3)"; for jigsaw they are "starting at |
| 244 | * (5,7)". So the sensible usage in both cases is to say |
| 245 | * "elimination within block %s" with one of these strings. |
| 246 | * |
| 247 | * Only blocknames itself needs individually freeing; it's all |
| 248 | * one block. |
| 249 | */ |
| 250 | char **blocknames; |
| 251 | #endif |
| 252 | }; |
| 253 | |
| 254 | struct game_state { |
| 255 | /* |
| 256 | * For historical reasons, I use `cr' to denote the overall |
| 257 | * width/height of the puzzle. It was a natural notation when |
| 258 | * all puzzles were divided into blocks in a grid, but doesn't |
| 259 | * really make much sense given jigsaw puzzles. However, the |
| 260 | * obvious `n' is heavily used in the solver to describe the |
| 261 | * index of a number being placed, so `cr' will have to stay. |
| 262 | */ |
| 263 | int cr; |
| 264 | struct block_structure *blocks; |
| 265 | struct block_structure *kblocks; /* Blocks for killer puzzles. */ |
| 266 | int xtype, killer; |
| 267 | digit *grid, *kgrid; |
| 268 | unsigned char *pencil; /* c*r*c*r elements */ |
| 269 | unsigned char *immutable; /* marks which digits are clues */ |
| 270 | int completed, cheated; |
| 271 | }; |
| 272 | |
| 273 | static game_params *default_params(void) |
| 274 | { |
| 275 | game_params *ret = snew(game_params); |
| 276 | |
| 277 | ret->c = ret->r = 3; |
| 278 | ret->xtype = FALSE; |
| 279 | ret->killer = FALSE; |
| 280 | ret->symm = SYMM_ROT2; /* a plausible default */ |
| 281 | ret->diff = DIFF_BLOCK; /* so is this */ |
| 282 | ret->kdiff = DIFF_KINTERSECT; /* so is this */ |
| 283 | |
| 284 | return ret; |
| 285 | } |
| 286 | |
| 287 | static void free_params(game_params *params) |
| 288 | { |
| 289 | sfree(params); |
| 290 | } |
| 291 | |
| 292 | static game_params *dup_params(game_params *params) |
| 293 | { |
| 294 | game_params *ret = snew(game_params); |
| 295 | *ret = *params; /* structure copy */ |
| 296 | return ret; |
| 297 | } |
| 298 | |
| 299 | static int game_fetch_preset(int i, char **name, game_params **params) |
| 300 | { |
| 301 | static struct { |
| 302 | char *title; |
| 303 | game_params params; |
| 304 | } presets[] = { |
| 305 | { "2x2 Trivial", { 2, 2, SYMM_ROT2, DIFF_BLOCK, DIFF_KMINMAX, FALSE, FALSE } }, |
| 306 | { "2x3 Basic", { 2, 3, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 307 | { "3x3 Trivial", { 3, 3, SYMM_ROT2, DIFF_BLOCK, DIFF_KMINMAX, FALSE, FALSE } }, |
| 308 | { "3x3 Basic", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 309 | { "3x3 Basic X", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, TRUE } }, |
| 310 | { "3x3 Intermediate", { 3, 3, SYMM_ROT2, DIFF_INTERSECT, DIFF_KMINMAX, FALSE, FALSE } }, |
| 311 | { "3x3 Advanced", { 3, 3, SYMM_ROT2, DIFF_SET, DIFF_KMINMAX, FALSE, FALSE } }, |
| 312 | { "3x3 Advanced X", { 3, 3, SYMM_ROT2, DIFF_SET, DIFF_KMINMAX, TRUE } }, |
| 313 | { "3x3 Extreme", { 3, 3, SYMM_ROT2, DIFF_EXTREME, DIFF_KMINMAX, FALSE, FALSE } }, |
| 314 | { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 315 | { "3x3 Killer", { 3, 3, SYMM_NONE, DIFF_BLOCK, DIFF_KINTERSECT, FALSE, TRUE } }, |
| 316 | { "9 Jigsaw Basic", { 9, 1, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 317 | { "9 Jigsaw Basic X", { 9, 1, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, TRUE } }, |
| 318 | { "9 Jigsaw Advanced", { 9, 1, SYMM_ROT2, DIFF_SET, DIFF_KMINMAX, FALSE, FALSE } }, |
| 319 | #ifndef SLOW_SYSTEM |
| 320 | { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 321 | { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE, DIFF_KMINMAX, FALSE, FALSE } }, |
| 322 | #endif |
| 323 | }; |
| 324 | |
| 325 | if (i < 0 || i >= lenof(presets)) |
| 326 | return FALSE; |
| 327 | |
| 328 | *name = dupstr(presets[i].title); |
| 329 | *params = dup_params(&presets[i].params); |
| 330 | |
| 331 | return TRUE; |
| 332 | } |
| 333 | |
| 334 | static void decode_params(game_params *ret, char const *string) |
| 335 | { |
| 336 | int seen_r = FALSE; |
| 337 | |
| 338 | ret->c = ret->r = atoi(string); |
| 339 | ret->xtype = FALSE; |
| 340 | ret->killer = FALSE; |
| 341 | while (*string && isdigit((unsigned char)*string)) string++; |
| 342 | if (*string == 'x') { |
| 343 | string++; |
| 344 | ret->r = atoi(string); |
| 345 | seen_r = TRUE; |
| 346 | while (*string && isdigit((unsigned char)*string)) string++; |
| 347 | } |
| 348 | while (*string) { |
| 349 | if (*string == 'j') { |
| 350 | string++; |
| 351 | if (seen_r) |
| 352 | ret->c *= ret->r; |
| 353 | ret->r = 1; |
| 354 | } else if (*string == 'x') { |
| 355 | string++; |
| 356 | ret->xtype = TRUE; |
| 357 | } else if (*string == 'k') { |
| 358 | string++; |
| 359 | ret->killer = TRUE; |
| 360 | } else if (*string == 'r' || *string == 'm' || *string == 'a') { |
| 361 | int sn, sc, sd; |
| 362 | sc = *string++; |
| 363 | if (sc == 'm' && *string == 'd') { |
| 364 | sd = TRUE; |
| 365 | string++; |
| 366 | } else { |
| 367 | sd = FALSE; |
| 368 | } |
| 369 | sn = atoi(string); |
| 370 | while (*string && isdigit((unsigned char)*string)) string++; |
| 371 | if (sc == 'm' && sn == 8) |
| 372 | ret->symm = SYMM_REF8; |
| 373 | if (sc == 'm' && sn == 4) |
| 374 | ret->symm = sd ? SYMM_REF4D : SYMM_REF4; |
| 375 | if (sc == 'm' && sn == 2) |
| 376 | ret->symm = sd ? SYMM_REF2D : SYMM_REF2; |
| 377 | if (sc == 'r' && sn == 4) |
| 378 | ret->symm = SYMM_ROT4; |
| 379 | if (sc == 'r' && sn == 2) |
| 380 | ret->symm = SYMM_ROT2; |
| 381 | if (sc == 'a') |
| 382 | ret->symm = SYMM_NONE; |
| 383 | } else if (*string == 'd') { |
| 384 | string++; |
| 385 | if (*string == 't') /* trivial */ |
| 386 | string++, ret->diff = DIFF_BLOCK; |
| 387 | else if (*string == 'b') /* basic */ |
| 388 | string++, ret->diff = DIFF_SIMPLE; |
| 389 | else if (*string == 'i') /* intermediate */ |
| 390 | string++, ret->diff = DIFF_INTERSECT; |
| 391 | else if (*string == 'a') /* advanced */ |
| 392 | string++, ret->diff = DIFF_SET; |
| 393 | else if (*string == 'e') /* extreme */ |
| 394 | string++, ret->diff = DIFF_EXTREME; |
| 395 | else if (*string == 'u') /* unreasonable */ |
| 396 | string++, ret->diff = DIFF_RECURSIVE; |
| 397 | } else |
| 398 | string++; /* eat unknown character */ |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | static char *encode_params(game_params *params, int full) |
| 403 | { |
| 404 | char str[80]; |
| 405 | |
| 406 | if (params->r > 1) |
| 407 | sprintf(str, "%dx%d", params->c, params->r); |
| 408 | else |
| 409 | sprintf(str, "%dj", params->c); |
| 410 | if (params->xtype) |
| 411 | strcat(str, "x"); |
| 412 | if (params->killer) |
| 413 | strcat(str, "k"); |
| 414 | |
| 415 | if (full) { |
| 416 | switch (params->symm) { |
| 417 | case SYMM_REF8: strcat(str, "m8"); break; |
| 418 | case SYMM_REF4: strcat(str, "m4"); break; |
| 419 | case SYMM_REF4D: strcat(str, "md4"); break; |
| 420 | case SYMM_REF2: strcat(str, "m2"); break; |
| 421 | case SYMM_REF2D: strcat(str, "md2"); break; |
| 422 | case SYMM_ROT4: strcat(str, "r4"); break; |
| 423 | /* case SYMM_ROT2: strcat(str, "r2"); break; [default] */ |
| 424 | case SYMM_NONE: strcat(str, "a"); break; |
| 425 | } |
| 426 | switch (params->diff) { |
| 427 | /* case DIFF_BLOCK: strcat(str, "dt"); break; [default] */ |
| 428 | case DIFF_SIMPLE: strcat(str, "db"); break; |
| 429 | case DIFF_INTERSECT: strcat(str, "di"); break; |
| 430 | case DIFF_SET: strcat(str, "da"); break; |
| 431 | case DIFF_EXTREME: strcat(str, "de"); break; |
| 432 | case DIFF_RECURSIVE: strcat(str, "du"); break; |
| 433 | } |
| 434 | } |
| 435 | return dupstr(str); |
| 436 | } |
| 437 | |
| 438 | static config_item *game_configure(game_params *params) |
| 439 | { |
| 440 | config_item *ret; |
| 441 | char buf[80]; |
| 442 | |
| 443 | ret = snewn(8, config_item); |
| 444 | |
| 445 | ret[0].name = "Columns of sub-blocks"; |
| 446 | ret[0].type = C_STRING; |
| 447 | sprintf(buf, "%d", params->c); |
| 448 | ret[0].sval = dupstr(buf); |
| 449 | ret[0].ival = 0; |
| 450 | |
| 451 | ret[1].name = "Rows of sub-blocks"; |
| 452 | ret[1].type = C_STRING; |
| 453 | sprintf(buf, "%d", params->r); |
| 454 | ret[1].sval = dupstr(buf); |
| 455 | ret[1].ival = 0; |
| 456 | |
| 457 | ret[2].name = "\"X\" (require every number in each main diagonal)"; |
| 458 | ret[2].type = C_BOOLEAN; |
| 459 | ret[2].sval = NULL; |
| 460 | ret[2].ival = params->xtype; |
| 461 | |
| 462 | ret[3].name = "Jigsaw (irregularly shaped sub-blocks)"; |
| 463 | ret[3].type = C_BOOLEAN; |
| 464 | ret[3].sval = NULL; |
| 465 | ret[3].ival = (params->r == 1); |
| 466 | |
| 467 | ret[4].name = "Killer (digit sums)"; |
| 468 | ret[4].type = C_BOOLEAN; |
| 469 | ret[4].sval = NULL; |
| 470 | ret[4].ival = params->killer; |
| 471 | |
| 472 | ret[5].name = "Symmetry"; |
| 473 | ret[5].type = C_CHOICES; |
| 474 | ret[5].sval = ":None:2-way rotation:4-way rotation:2-way mirror:" |
| 475 | "2-way diagonal mirror:4-way mirror:4-way diagonal mirror:" |
| 476 | "8-way mirror"; |
| 477 | ret[5].ival = params->symm; |
| 478 | |
| 479 | ret[6].name = "Difficulty"; |
| 480 | ret[6].type = C_CHOICES; |
| 481 | ret[6].sval = ":Trivial:Basic:Intermediate:Advanced:Extreme:Unreasonable"; |
| 482 | ret[6].ival = params->diff; |
| 483 | |
| 484 | ret[7].name = NULL; |
| 485 | ret[7].type = C_END; |
| 486 | ret[7].sval = NULL; |
| 487 | ret[7].ival = 0; |
| 488 | |
| 489 | return ret; |
| 490 | } |
| 491 | |
| 492 | static game_params *custom_params(config_item *cfg) |
| 493 | { |
| 494 | game_params *ret = snew(game_params); |
| 495 | |
| 496 | ret->c = atoi(cfg[0].sval); |
| 497 | ret->r = atoi(cfg[1].sval); |
| 498 | ret->xtype = cfg[2].ival; |
| 499 | if (cfg[3].ival) { |
| 500 | ret->c *= ret->r; |
| 501 | ret->r = 1; |
| 502 | } |
| 503 | ret->killer = cfg[4].ival; |
| 504 | ret->symm = cfg[5].ival; |
| 505 | ret->diff = cfg[6].ival; |
| 506 | ret->kdiff = DIFF_KINTERSECT; |
| 507 | |
| 508 | return ret; |
| 509 | } |
| 510 | |
| 511 | static char *validate_params(game_params *params, int full) |
| 512 | { |
| 513 | if (params->c < 2) |
| 514 | return "Both dimensions must be at least 2"; |
| 515 | if (params->c > ORDER_MAX || params->r > ORDER_MAX) |
| 516 | return "Dimensions greater than "STR(ORDER_MAX)" are not supported"; |
| 517 | if ((params->c * params->r) > 31) |
| 518 | return "Unable to support more than 31 distinct symbols in a puzzle"; |
| 519 | if (params->killer && params->c * params->r > 9) |
| 520 | return "Killer puzzle dimensions must be smaller than 10."; |
| 521 | return NULL; |
| 522 | } |
| 523 | |
| 524 | /* |
| 525 | * ---------------------------------------------------------------------- |
| 526 | * Block structure functions. |
| 527 | */ |
| 528 | |
| 529 | static struct block_structure *alloc_block_structure(int c, int r, int area, |
| 530 | int max_nr_squares, |
| 531 | int nr_blocks) |
| 532 | { |
| 533 | int i; |
| 534 | struct block_structure *b = snew(struct block_structure); |
| 535 | |
| 536 | b->refcount = 1; |
| 537 | b->nr_blocks = nr_blocks; |
| 538 | b->max_nr_squares = max_nr_squares; |
| 539 | b->c = c; b->r = r; b->area = area; |
| 540 | b->whichblock = snewn(area, int); |
| 541 | b->blocks_data = snewn(nr_blocks * max_nr_squares, int); |
| 542 | b->blocks = snewn(nr_blocks, int *); |
| 543 | b->nr_squares = snewn(nr_blocks, int); |
| 544 | |
| 545 | for (i = 0; i < nr_blocks; i++) |
| 546 | b->blocks[i] = b->blocks_data + i*max_nr_squares; |
| 547 | |
| 548 | #ifdef STANDALONE_SOLVER |
| 549 | b->blocknames = (char **)smalloc(c*r*(sizeof(char *)+80)); |
| 550 | for (i = 0; i < c * r; i++) |
| 551 | b->blocknames[i] = NULL; |
| 552 | #endif |
| 553 | return b; |
| 554 | } |
| 555 | |
| 556 | static void free_block_structure(struct block_structure *b) |
| 557 | { |
| 558 | if (--b->refcount == 0) { |
| 559 | sfree(b->whichblock); |
| 560 | sfree(b->blocks); |
| 561 | sfree(b->blocks_data); |
| 562 | #ifdef STANDALONE_SOLVER |
| 563 | sfree(b->blocknames); |
| 564 | #endif |
| 565 | sfree(b->nr_squares); |
| 566 | sfree(b); |
| 567 | } |
| 568 | } |
| 569 | |
| 570 | static struct block_structure *dup_block_structure(struct block_structure *b) |
| 571 | { |
| 572 | struct block_structure *nb; |
| 573 | int i; |
| 574 | |
| 575 | nb = alloc_block_structure(b->c, b->r, b->area, b->max_nr_squares, |
| 576 | b->nr_blocks); |
| 577 | memcpy(nb->nr_squares, b->nr_squares, b->nr_blocks * sizeof *b->nr_squares); |
| 578 | memcpy(nb->whichblock, b->whichblock, b->area * sizeof *b->whichblock); |
| 579 | memcpy(nb->blocks_data, b->blocks_data, |
| 580 | b->nr_blocks * b->max_nr_squares * sizeof *b->blocks_data); |
| 581 | for (i = 0; i < b->nr_blocks; i++) |
| 582 | nb->blocks[i] = nb->blocks_data + i*nb->max_nr_squares; |
| 583 | |
| 584 | #ifdef STANDALONE_SOLVER |
| 585 | memcpy(nb->blocknames, b->blocknames, b->c * b->r *(sizeof(char *)+80)); |
| 586 | { |
| 587 | int i; |
| 588 | for (i = 0; i < b->c * b->r; i++) |
| 589 | if (b->blocknames[i] == NULL) |
| 590 | nb->blocknames[i] = NULL; |
| 591 | else |
| 592 | nb->blocknames[i] = ((char *)nb->blocknames) + (b->blocknames[i] - (char *)b->blocknames); |
| 593 | } |
| 594 | #endif |
| 595 | return nb; |
| 596 | } |
| 597 | |
| 598 | static void split_block(struct block_structure *b, int *squares, int nr_squares) |
| 599 | { |
| 600 | int i, j; |
| 601 | int previous_block = b->whichblock[squares[0]]; |
| 602 | int newblock = b->nr_blocks; |
| 603 | |
| 604 | assert(b->max_nr_squares >= nr_squares); |
| 605 | assert(b->nr_squares[previous_block] > nr_squares); |
| 606 | |
| 607 | b->nr_blocks++; |
| 608 | b->blocks_data = sresize(b->blocks_data, |
| 609 | b->nr_blocks * b->max_nr_squares, int); |
| 610 | b->nr_squares = sresize(b->nr_squares, b->nr_blocks, int); |
| 611 | sfree(b->blocks); |
| 612 | b->blocks = snewn(b->nr_blocks, int *); |
| 613 | for (i = 0; i < b->nr_blocks; i++) |
| 614 | b->blocks[i] = b->blocks_data + i*b->max_nr_squares; |
| 615 | for (i = 0; i < nr_squares; i++) { |
| 616 | assert(b->whichblock[squares[i]] == previous_block); |
| 617 | b->whichblock[squares[i]] = newblock; |
| 618 | b->blocks[newblock][i] = squares[i]; |
| 619 | } |
| 620 | for (i = j = 0; i < b->nr_squares[previous_block]; i++) { |
| 621 | int k; |
| 622 | int sq = b->blocks[previous_block][i]; |
| 623 | for (k = 0; k < nr_squares; k++) |
| 624 | if (squares[k] == sq) |
| 625 | break; |
| 626 | if (k == nr_squares) |
| 627 | b->blocks[previous_block][j++] = sq; |
| 628 | } |
| 629 | b->nr_squares[previous_block] -= nr_squares; |
| 630 | b->nr_squares[newblock] = nr_squares; |
| 631 | } |
| 632 | |
| 633 | static void remove_from_block(struct block_structure *blocks, int b, int n) |
| 634 | { |
| 635 | int i, j; |
| 636 | blocks->whichblock[n] = -1; |
| 637 | for (i = j = 0; i < blocks->nr_squares[b]; i++) |
| 638 | if (blocks->blocks[b][i] != n) |
| 639 | blocks->blocks[b][j++] = blocks->blocks[b][i]; |
| 640 | assert(j+1 == i); |
| 641 | blocks->nr_squares[b]--; |
| 642 | } |
| 643 | |
| 644 | /* ---------------------------------------------------------------------- |
| 645 | * Solver. |
| 646 | * |
| 647 | * This solver is used for two purposes: |
| 648 | * + to check solubility of a grid as we gradually remove numbers |
| 649 | * from it |
| 650 | * + to solve an externally generated puzzle when the user selects |
| 651 | * `Solve'. |
| 652 | * |
| 653 | * It supports a variety of specific modes of reasoning. By |
| 654 | * enabling or disabling subsets of these modes we can arrange a |
| 655 | * range of difficulty levels. |
| 656 | */ |
| 657 | |
| 658 | /* |
| 659 | * Modes of reasoning currently supported: |
| 660 | * |
| 661 | * - Positional elimination: a number must go in a particular |
| 662 | * square because all the other empty squares in a given |
| 663 | * row/col/blk are ruled out. |
| 664 | * |
| 665 | * - Killer minmax elimination: for killer-type puzzles, a number |
| 666 | * is impossible if choosing it would cause the sum in a killer |
| 667 | * region to be guaranteed to be too large or too small. |
| 668 | * |
| 669 | * - Numeric elimination: a square must have a particular number |
| 670 | * in because all the other numbers that could go in it are |
| 671 | * ruled out. |
| 672 | * |
| 673 | * - Intersectional analysis: given two domains which overlap |
| 674 | * (hence one must be a block, and the other can be a row or |
| 675 | * col), if the possible locations for a particular number in |
| 676 | * one of the domains can be narrowed down to the overlap, then |
| 677 | * that number can be ruled out everywhere but the overlap in |
| 678 | * the other domain too. |
| 679 | * |
| 680 | * - Set elimination: if there is a subset of the empty squares |
| 681 | * within a domain such that the union of the possible numbers |
| 682 | * in that subset has the same size as the subset itself, then |
| 683 | * those numbers can be ruled out everywhere else in the domain. |
| 684 | * (For example, if there are five empty squares and the |
| 685 | * possible numbers in each are 12, 23, 13, 134 and 1345, then |
| 686 | * the first three empty squares form such a subset: the numbers |
| 687 | * 1, 2 and 3 _must_ be in those three squares in some |
| 688 | * permutation, and hence we can deduce none of them can be in |
| 689 | * the fourth or fifth squares.) |
| 690 | * + You can also see this the other way round, concentrating |
| 691 | * on numbers rather than squares: if there is a subset of |
| 692 | * the unplaced numbers within a domain such that the union |
| 693 | * of all their possible positions has the same size as the |
| 694 | * subset itself, then all other numbers can be ruled out for |
| 695 | * those positions. However, it turns out that this is |
| 696 | * exactly equivalent to the first formulation at all times: |
| 697 | * there is a 1-1 correspondence between suitable subsets of |
| 698 | * the unplaced numbers and suitable subsets of the unfilled |
| 699 | * places, found by taking the _complement_ of the union of |
| 700 | * the numbers' possible positions (or the spaces' possible |
| 701 | * contents). |
| 702 | * |
| 703 | * - Forcing chains (see comment for solver_forcing().) |
| 704 | * |
| 705 | * - Recursion. If all else fails, we pick one of the currently |
| 706 | * most constrained empty squares and take a random guess at its |
| 707 | * contents, then continue solving on that basis and see if we |
| 708 | * get any further. |
| 709 | */ |
| 710 | |
| 711 | struct solver_usage { |
| 712 | int cr; |
| 713 | struct block_structure *blocks, *kblocks, *extra_cages; |
| 714 | /* |
| 715 | * We set up a cubic array, indexed by x, y and digit; each |
| 716 | * element of this array is TRUE or FALSE according to whether |
| 717 | * or not that digit _could_ in principle go in that position. |
| 718 | * |
| 719 | * The way to index this array is cube[(y*cr+x)*cr+n-1]; there |
| 720 | * are macros below to help with this. |
| 721 | */ |
| 722 | unsigned char *cube; |
| 723 | /* |
| 724 | * This is the grid in which we write down our final |
| 725 | * deductions. y-coordinates in here are _not_ transformed. |
| 726 | */ |
| 727 | digit *grid; |
| 728 | /* |
| 729 | * For killer-type puzzles, kclues holds the secondary clue for |
| 730 | * each cage. For derived cages, the clue is in extra_clues. |
| 731 | */ |
| 732 | digit *kclues, *extra_clues; |
| 733 | /* |
| 734 | * Now we keep track, at a slightly higher level, of what we |
| 735 | * have yet to work out, to prevent doing the same deduction |
| 736 | * many times. |
| 737 | */ |
| 738 | /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ |
| 739 | unsigned char *row; |
| 740 | /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ |
| 741 | unsigned char *col; |
| 742 | /* blk[i*cr+n-1] TRUE if digit n has been placed in block i */ |
| 743 | unsigned char *blk; |
| 744 | /* diag[i*cr+n-1] TRUE if digit n has been placed in diagonal i */ |
| 745 | unsigned char *diag; /* diag 0 is \, 1 is / */ |
| 746 | |
| 747 | int *regions; |
| 748 | int nr_regions; |
| 749 | int **sq2region; |
| 750 | }; |
| 751 | #define cubepos2(xy,n) ((xy)*usage->cr+(n)-1) |
| 752 | #define cubepos(x,y,n) cubepos2((y)*usage->cr+(x),n) |
| 753 | #define cube(x,y,n) (usage->cube[cubepos(x,y,n)]) |
| 754 | #define cube2(xy,n) (usage->cube[cubepos2(xy,n)]) |
| 755 | |
| 756 | #define ondiag0(xy) ((xy) % (cr+1) == 0) |
| 757 | #define ondiag1(xy) ((xy) % (cr-1) == 0 && (xy) > 0 && (xy) < cr*cr-1) |
| 758 | #define diag0(i) ((i) * (cr+1)) |
| 759 | #define diag1(i) ((i+1) * (cr-1)) |
| 760 | |
| 761 | /* |
| 762 | * Function called when we are certain that a particular square has |
| 763 | * a particular number in it. The y-coordinate passed in here is |
| 764 | * transformed. |
| 765 | */ |
| 766 | static void solver_place(struct solver_usage *usage, int x, int y, int n) |
| 767 | { |
| 768 | int cr = usage->cr; |
| 769 | int sqindex = y*cr+x; |
| 770 | int i, bi; |
| 771 | |
| 772 | assert(cube(x,y,n)); |
| 773 | |
| 774 | /* |
| 775 | * Rule out all other numbers in this square. |
| 776 | */ |
| 777 | for (i = 1; i <= cr; i++) |
| 778 | if (i != n) |
| 779 | cube(x,y,i) = FALSE; |
| 780 | |
| 781 | /* |
| 782 | * Rule out this number in all other positions in the row. |
| 783 | */ |
| 784 | for (i = 0; i < cr; i++) |
| 785 | if (i != y) |
| 786 | cube(x,i,n) = FALSE; |
| 787 | |
| 788 | /* |
| 789 | * Rule out this number in all other positions in the column. |
| 790 | */ |
| 791 | for (i = 0; i < cr; i++) |
| 792 | if (i != x) |
| 793 | cube(i,y,n) = FALSE; |
| 794 | |
| 795 | /* |
| 796 | * Rule out this number in all other positions in the block. |
| 797 | */ |
| 798 | bi = usage->blocks->whichblock[sqindex]; |
| 799 | for (i = 0; i < cr; i++) { |
| 800 | int bp = usage->blocks->blocks[bi][i]; |
| 801 | if (bp != sqindex) |
| 802 | cube2(bp,n) = FALSE; |
| 803 | } |
| 804 | |
| 805 | /* |
| 806 | * Enter the number in the result grid. |
| 807 | */ |
| 808 | usage->grid[sqindex] = n; |
| 809 | |
| 810 | /* |
| 811 | * Cross out this number from the list of numbers left to place |
| 812 | * in its row, its column and its block. |
| 813 | */ |
| 814 | usage->row[y*cr+n-1] = usage->col[x*cr+n-1] = |
| 815 | usage->blk[bi*cr+n-1] = TRUE; |
| 816 | |
| 817 | if (usage->diag) { |
| 818 | if (ondiag0(sqindex)) { |
| 819 | for (i = 0; i < cr; i++) |
| 820 | if (diag0(i) != sqindex) |
| 821 | cube2(diag0(i),n) = FALSE; |
| 822 | usage->diag[n-1] = TRUE; |
| 823 | } |
| 824 | if (ondiag1(sqindex)) { |
| 825 | for (i = 0; i < cr; i++) |
| 826 | if (diag1(i) != sqindex) |
| 827 | cube2(diag1(i),n) = FALSE; |
| 828 | usage->diag[cr+n-1] = TRUE; |
| 829 | } |
| 830 | } |
| 831 | } |
| 832 | |
| 833 | static int solver_elim(struct solver_usage *usage, int *indices |
| 834 | #ifdef STANDALONE_SOLVER |
| 835 | , char *fmt, ... |
| 836 | #endif |
| 837 | ) |
| 838 | { |
| 839 | int cr = usage->cr; |
| 840 | int fpos, m, i; |
| 841 | |
| 842 | /* |
| 843 | * Count the number of set bits within this section of the |
| 844 | * cube. |
| 845 | */ |
| 846 | m = 0; |
| 847 | fpos = -1; |
| 848 | for (i = 0; i < cr; i++) |
| 849 | if (usage->cube[indices[i]]) { |
| 850 | fpos = indices[i]; |
| 851 | m++; |
| 852 | } |
| 853 | |
| 854 | if (m == 1) { |
| 855 | int x, y, n; |
| 856 | assert(fpos >= 0); |
| 857 | |
| 858 | n = 1 + fpos % cr; |
| 859 | x = fpos / cr; |
| 860 | y = x / cr; |
| 861 | x %= cr; |
| 862 | |
| 863 | if (!usage->grid[y*cr+x]) { |
| 864 | #ifdef STANDALONE_SOLVER |
| 865 | if (solver_show_working) { |
| 866 | va_list ap; |
| 867 | printf("%*s", solver_recurse_depth*4, ""); |
| 868 | va_start(ap, fmt); |
| 869 | vprintf(fmt, ap); |
| 870 | va_end(ap); |
| 871 | printf(":\n%*s placing %d at (%d,%d)\n", |
| 872 | solver_recurse_depth*4, "", n, 1+x, 1+y); |
| 873 | } |
| 874 | #endif |
| 875 | solver_place(usage, x, y, n); |
| 876 | return +1; |
| 877 | } |
| 878 | } else if (m == 0) { |
| 879 | #ifdef STANDALONE_SOLVER |
| 880 | if (solver_show_working) { |
| 881 | va_list ap; |
| 882 | printf("%*s", solver_recurse_depth*4, ""); |
| 883 | va_start(ap, fmt); |
| 884 | vprintf(fmt, ap); |
| 885 | va_end(ap); |
| 886 | printf(":\n%*s no possibilities available\n", |
| 887 | solver_recurse_depth*4, ""); |
| 888 | } |
| 889 | #endif |
| 890 | return -1; |
| 891 | } |
| 892 | |
| 893 | return 0; |
| 894 | } |
| 895 | |
| 896 | static int solver_intersect(struct solver_usage *usage, |
| 897 | int *indices1, int *indices2 |
| 898 | #ifdef STANDALONE_SOLVER |
| 899 | , char *fmt, ... |
| 900 | #endif |
| 901 | ) |
| 902 | { |
| 903 | int cr = usage->cr; |
| 904 | int ret, i, j; |
| 905 | |
| 906 | /* |
| 907 | * Loop over the first domain and see if there's any set bit |
| 908 | * not also in the second. |
| 909 | */ |
| 910 | for (i = j = 0; i < cr; i++) { |
| 911 | int p = indices1[i]; |
| 912 | while (j < cr && indices2[j] < p) |
| 913 | j++; |
| 914 | if (usage->cube[p]) { |
| 915 | if (j < cr && indices2[j] == p) |
| 916 | continue; /* both domains contain this index */ |
| 917 | else |
| 918 | return 0; /* there is, so we can't deduce */ |
| 919 | } |
| 920 | } |
| 921 | |
| 922 | /* |
| 923 | * We have determined that all set bits in the first domain are |
| 924 | * within its overlap with the second. So loop over the second |
| 925 | * domain and remove all set bits that aren't also in that |
| 926 | * overlap; return +1 iff we actually _did_ anything. |
| 927 | */ |
| 928 | ret = 0; |
| 929 | for (i = j = 0; i < cr; i++) { |
| 930 | int p = indices2[i]; |
| 931 | while (j < cr && indices1[j] < p) |
| 932 | j++; |
| 933 | if (usage->cube[p] && (j >= cr || indices1[j] != p)) { |
| 934 | #ifdef STANDALONE_SOLVER |
| 935 | if (solver_show_working) { |
| 936 | int px, py, pn; |
| 937 | |
| 938 | if (!ret) { |
| 939 | va_list ap; |
| 940 | printf("%*s", solver_recurse_depth*4, ""); |
| 941 | va_start(ap, fmt); |
| 942 | vprintf(fmt, ap); |
| 943 | va_end(ap); |
| 944 | printf(":\n"); |
| 945 | } |
| 946 | |
| 947 | pn = 1 + p % cr; |
| 948 | px = p / cr; |
| 949 | py = px / cr; |
| 950 | px %= cr; |
| 951 | |
| 952 | printf("%*s ruling out %d at (%d,%d)\n", |
| 953 | solver_recurse_depth*4, "", pn, 1+px, 1+py); |
| 954 | } |
| 955 | #endif |
| 956 | ret = +1; /* we did something */ |
| 957 | usage->cube[p] = 0; |
| 958 | } |
| 959 | } |
| 960 | |
| 961 | return ret; |
| 962 | } |
| 963 | |
| 964 | struct solver_scratch { |
| 965 | unsigned char *grid, *rowidx, *colidx, *set; |
| 966 | int *neighbours, *bfsqueue; |
| 967 | int *indexlist, *indexlist2; |
| 968 | #ifdef STANDALONE_SOLVER |
| 969 | int *bfsprev; |
| 970 | #endif |
| 971 | }; |
| 972 | |
| 973 | static int solver_set(struct solver_usage *usage, |
| 974 | struct solver_scratch *scratch, |
| 975 | int *indices |
| 976 | #ifdef STANDALONE_SOLVER |
| 977 | , char *fmt, ... |
| 978 | #endif |
| 979 | ) |
| 980 | { |
| 981 | int cr = usage->cr; |
| 982 | int i, j, n, count; |
| 983 | unsigned char *grid = scratch->grid; |
| 984 | unsigned char *rowidx = scratch->rowidx; |
| 985 | unsigned char *colidx = scratch->colidx; |
| 986 | unsigned char *set = scratch->set; |
| 987 | |
| 988 | /* |
| 989 | * We are passed a cr-by-cr matrix of booleans. Our first job |
| 990 | * is to winnow it by finding any definite placements - i.e. |
| 991 | * any row with a solitary 1 - and discarding that row and the |
| 992 | * column containing the 1. |
| 993 | */ |
| 994 | memset(rowidx, TRUE, cr); |
| 995 | memset(colidx, TRUE, cr); |
| 996 | for (i = 0; i < cr; i++) { |
| 997 | int count = 0, first = -1; |
| 998 | for (j = 0; j < cr; j++) |
| 999 | if (usage->cube[indices[i*cr+j]]) |
| 1000 | first = j, count++; |
| 1001 | |
| 1002 | /* |
| 1003 | * If count == 0, then there's a row with no 1s at all and |
| 1004 | * the puzzle is internally inconsistent. However, we ought |
| 1005 | * to have caught this already during the simpler reasoning |
| 1006 | * methods, so we can safely fail an assertion if we reach |
| 1007 | * this point here. |
| 1008 | */ |
| 1009 | assert(count > 0); |
| 1010 | if (count == 1) |
| 1011 | rowidx[i] = colidx[first] = FALSE; |
| 1012 | } |
| 1013 | |
| 1014 | /* |
| 1015 | * Convert each of rowidx/colidx from a list of 0s and 1s to a |
| 1016 | * list of the indices of the 1s. |
| 1017 | */ |
| 1018 | for (i = j = 0; i < cr; i++) |
| 1019 | if (rowidx[i]) |
| 1020 | rowidx[j++] = i; |
| 1021 | n = j; |
| 1022 | for (i = j = 0; i < cr; i++) |
| 1023 | if (colidx[i]) |
| 1024 | colidx[j++] = i; |
| 1025 | assert(n == j); |
| 1026 | |
| 1027 | /* |
| 1028 | * And create the smaller matrix. |
| 1029 | */ |
| 1030 | for (i = 0; i < n; i++) |
| 1031 | for (j = 0; j < n; j++) |
| 1032 | grid[i*cr+j] = usage->cube[indices[rowidx[i]*cr+colidx[j]]]; |
| 1033 | |
| 1034 | /* |
| 1035 | * Having done that, we now have a matrix in which every row |
| 1036 | * has at least two 1s in. Now we search to see if we can find |
| 1037 | * a rectangle of zeroes (in the set-theoretic sense of |
| 1038 | * `rectangle', i.e. a subset of rows crossed with a subset of |
| 1039 | * columns) whose width and height add up to n. |
| 1040 | */ |
| 1041 | |
| 1042 | memset(set, 0, n); |
| 1043 | count = 0; |
| 1044 | while (1) { |
| 1045 | /* |
| 1046 | * We have a candidate set. If its size is <=1 or >=n-1 |
| 1047 | * then we move on immediately. |
| 1048 | */ |
| 1049 | if (count > 1 && count < n-1) { |
| 1050 | /* |
| 1051 | * The number of rows we need is n-count. See if we can |
| 1052 | * find that many rows which each have a zero in all |
| 1053 | * the positions listed in `set'. |
| 1054 | */ |
| 1055 | int rows = 0; |
| 1056 | for (i = 0; i < n; i++) { |
| 1057 | int ok = TRUE; |
| 1058 | for (j = 0; j < n; j++) |
| 1059 | if (set[j] && grid[i*cr+j]) { |
| 1060 | ok = FALSE; |
| 1061 | break; |
| 1062 | } |
| 1063 | if (ok) |
| 1064 | rows++; |
| 1065 | } |
| 1066 | |
| 1067 | /* |
| 1068 | * We expect never to be able to get _more_ than |
| 1069 | * n-count suitable rows: this would imply that (for |
| 1070 | * example) there are four numbers which between them |
| 1071 | * have at most three possible positions, and hence it |
| 1072 | * indicates a faulty deduction before this point or |
| 1073 | * even a bogus clue. |
| 1074 | */ |
| 1075 | if (rows > n - count) { |
| 1076 | #ifdef STANDALONE_SOLVER |
| 1077 | if (solver_show_working) { |
| 1078 | va_list ap; |
| 1079 | printf("%*s", solver_recurse_depth*4, |
| 1080 | ""); |
| 1081 | va_start(ap, fmt); |
| 1082 | vprintf(fmt, ap); |
| 1083 | va_end(ap); |
| 1084 | printf(":\n%*s contradiction reached\n", |
| 1085 | solver_recurse_depth*4, ""); |
| 1086 | } |
| 1087 | #endif |
| 1088 | return -1; |
| 1089 | } |
| 1090 | |
| 1091 | if (rows >= n - count) { |
| 1092 | int progress = FALSE; |
| 1093 | |
| 1094 | /* |
| 1095 | * We've got one! Now, for each row which _doesn't_ |
| 1096 | * satisfy the criterion, eliminate all its set |
| 1097 | * bits in the positions _not_ listed in `set'. |
| 1098 | * Return +1 (meaning progress has been made) if we |
| 1099 | * successfully eliminated anything at all. |
| 1100 | * |
| 1101 | * This involves referring back through |
| 1102 | * rowidx/colidx in order to work out which actual |
| 1103 | * positions in the cube to meddle with. |
| 1104 | */ |
| 1105 | for (i = 0; i < n; i++) { |
| 1106 | int ok = TRUE; |
| 1107 | for (j = 0; j < n; j++) |
| 1108 | if (set[j] && grid[i*cr+j]) { |
| 1109 | ok = FALSE; |
| 1110 | break; |
| 1111 | } |
| 1112 | if (!ok) { |
| 1113 | for (j = 0; j < n; j++) |
| 1114 | if (!set[j] && grid[i*cr+j]) { |
| 1115 | int fpos = indices[rowidx[i]*cr+colidx[j]]; |
| 1116 | #ifdef STANDALONE_SOLVER |
| 1117 | if (solver_show_working) { |
| 1118 | int px, py, pn; |
| 1119 | |
| 1120 | if (!progress) { |
| 1121 | va_list ap; |
| 1122 | printf("%*s", solver_recurse_depth*4, |
| 1123 | ""); |
| 1124 | va_start(ap, fmt); |
| 1125 | vprintf(fmt, ap); |
| 1126 | va_end(ap); |
| 1127 | printf(":\n"); |
| 1128 | } |
| 1129 | |
| 1130 | pn = 1 + fpos % cr; |
| 1131 | px = fpos / cr; |
| 1132 | py = px / cr; |
| 1133 | px %= cr; |
| 1134 | |
| 1135 | printf("%*s ruling out %d at (%d,%d)\n", |
| 1136 | solver_recurse_depth*4, "", |
| 1137 | pn, 1+px, 1+py); |
| 1138 | } |
| 1139 | #endif |
| 1140 | progress = TRUE; |
| 1141 | usage->cube[fpos] = FALSE; |
| 1142 | } |
| 1143 | } |
| 1144 | } |
| 1145 | |
| 1146 | if (progress) { |
| 1147 | return +1; |
| 1148 | } |
| 1149 | } |
| 1150 | } |
| 1151 | |
| 1152 | /* |
| 1153 | * Binary increment: change the rightmost 0 to a 1, and |
| 1154 | * change all 1s to the right of it to 0s. |
| 1155 | */ |
| 1156 | i = n; |
| 1157 | while (i > 0 && set[i-1]) |
| 1158 | set[--i] = 0, count--; |
| 1159 | if (i > 0) |
| 1160 | set[--i] = 1, count++; |
| 1161 | else |
| 1162 | break; /* done */ |
| 1163 | } |
| 1164 | |
| 1165 | return 0; |
| 1166 | } |
| 1167 | |
| 1168 | /* |
| 1169 | * Look for forcing chains. A forcing chain is a path of |
| 1170 | * pairwise-exclusive squares (i.e. each pair of adjacent squares |
| 1171 | * in the path are in the same row, column or block) with the |
| 1172 | * following properties: |
| 1173 | * |
| 1174 | * (a) Each square on the path has precisely two possible numbers. |
| 1175 | * |
| 1176 | * (b) Each pair of squares which are adjacent on the path share |
| 1177 | * at least one possible number in common. |
| 1178 | * |
| 1179 | * (c) Each square in the middle of the path shares _both_ of its |
| 1180 | * numbers with at least one of its neighbours (not the same |
| 1181 | * one with both neighbours). |
| 1182 | * |
| 1183 | * These together imply that at least one of the possible number |
| 1184 | * choices at one end of the path forces _all_ the rest of the |
| 1185 | * numbers along the path. In order to make real use of this, we |
| 1186 | * need further properties: |
| 1187 | * |
| 1188 | * (c) Ruling out some number N from the square at one end of the |
| 1189 | * path forces the square at the other end to take the same |
| 1190 | * number N. |
| 1191 | * |
| 1192 | * (d) The two end squares are both in line with some third |
| 1193 | * square. |
| 1194 | * |
| 1195 | * (e) That third square currently has N as a possibility. |
| 1196 | * |
| 1197 | * If we can find all of that lot, we can deduce that at least one |
| 1198 | * of the two ends of the forcing chain has number N, and that |
| 1199 | * therefore the mutually adjacent third square does not. |
| 1200 | * |
| 1201 | * To find forcing chains, we're going to start a bfs at each |
| 1202 | * suitable square, once for each of its two possible numbers. |
| 1203 | */ |
| 1204 | static int solver_forcing(struct solver_usage *usage, |
| 1205 | struct solver_scratch *scratch) |
| 1206 | { |
| 1207 | int cr = usage->cr; |
| 1208 | int *bfsqueue = scratch->bfsqueue; |
| 1209 | #ifdef STANDALONE_SOLVER |
| 1210 | int *bfsprev = scratch->bfsprev; |
| 1211 | #endif |
| 1212 | unsigned char *number = scratch->grid; |
| 1213 | int *neighbours = scratch->neighbours; |
| 1214 | int x, y; |
| 1215 | |
| 1216 | for (y = 0; y < cr; y++) |
| 1217 | for (x = 0; x < cr; x++) { |
| 1218 | int count, t, n; |
| 1219 | |
| 1220 | /* |
| 1221 | * If this square doesn't have exactly two candidate |
| 1222 | * numbers, don't try it. |
| 1223 | * |
| 1224 | * In this loop we also sum the candidate numbers, |
| 1225 | * which is a nasty hack to allow us to quickly find |
| 1226 | * `the other one' (since we will shortly know there |
| 1227 | * are exactly two). |
| 1228 | */ |
| 1229 | for (count = t = 0, n = 1; n <= cr; n++) |
| 1230 | if (cube(x, y, n)) |
| 1231 | count++, t += n; |
| 1232 | if (count != 2) |
| 1233 | continue; |
| 1234 | |
| 1235 | /* |
| 1236 | * Now attempt a bfs for each candidate. |
| 1237 | */ |
| 1238 | for (n = 1; n <= cr; n++) |
| 1239 | if (cube(x, y, n)) { |
| 1240 | int orign, currn, head, tail; |
| 1241 | |
| 1242 | /* |
| 1243 | * Begin a bfs. |
| 1244 | */ |
| 1245 | orign = n; |
| 1246 | |
| 1247 | memset(number, cr+1, cr*cr); |
| 1248 | head = tail = 0; |
| 1249 | bfsqueue[tail++] = y*cr+x; |
| 1250 | #ifdef STANDALONE_SOLVER |
| 1251 | bfsprev[y*cr+x] = -1; |
| 1252 | #endif |
| 1253 | number[y*cr+x] = t - n; |
| 1254 | |
| 1255 | while (head < tail) { |
| 1256 | int xx, yy, nneighbours, xt, yt, i; |
| 1257 | |
| 1258 | xx = bfsqueue[head++]; |
| 1259 | yy = xx / cr; |
| 1260 | xx %= cr; |
| 1261 | |
| 1262 | currn = number[yy*cr+xx]; |
| 1263 | |
| 1264 | /* |
| 1265 | * Find neighbours of yy,xx. |
| 1266 | */ |
| 1267 | nneighbours = 0; |
| 1268 | for (yt = 0; yt < cr; yt++) |
| 1269 | neighbours[nneighbours++] = yt*cr+xx; |
| 1270 | for (xt = 0; xt < cr; xt++) |
| 1271 | neighbours[nneighbours++] = yy*cr+xt; |
| 1272 | xt = usage->blocks->whichblock[yy*cr+xx]; |
| 1273 | for (yt = 0; yt < cr; yt++) |
| 1274 | neighbours[nneighbours++] = usage->blocks->blocks[xt][yt]; |
| 1275 | if (usage->diag) { |
| 1276 | int sqindex = yy*cr+xx; |
| 1277 | if (ondiag0(sqindex)) { |
| 1278 | for (i = 0; i < cr; i++) |
| 1279 | neighbours[nneighbours++] = diag0(i); |
| 1280 | } |
| 1281 | if (ondiag1(sqindex)) { |
| 1282 | for (i = 0; i < cr; i++) |
| 1283 | neighbours[nneighbours++] = diag1(i); |
| 1284 | } |
| 1285 | } |
| 1286 | |
| 1287 | /* |
| 1288 | * Try visiting each of those neighbours. |
| 1289 | */ |
| 1290 | for (i = 0; i < nneighbours; i++) { |
| 1291 | int cc, tt, nn; |
| 1292 | |
| 1293 | xt = neighbours[i] % cr; |
| 1294 | yt = neighbours[i] / cr; |
| 1295 | |
| 1296 | /* |
| 1297 | * We need this square to not be |
| 1298 | * already visited, and to include |
| 1299 | * currn as a possible number. |
| 1300 | */ |
| 1301 | if (number[yt*cr+xt] <= cr) |
| 1302 | continue; |
| 1303 | if (!cube(xt, yt, currn)) |
| 1304 | continue; |
| 1305 | |
| 1306 | /* |
| 1307 | * Don't visit _this_ square a second |
| 1308 | * time! |
| 1309 | */ |
| 1310 | if (xt == xx && yt == yy) |
| 1311 | continue; |
| 1312 | |
| 1313 | /* |
| 1314 | * To continue with the bfs, we need |
| 1315 | * this square to have exactly two |
| 1316 | * possible numbers. |
| 1317 | */ |
| 1318 | for (cc = tt = 0, nn = 1; nn <= cr; nn++) |
| 1319 | if (cube(xt, yt, nn)) |
| 1320 | cc++, tt += nn; |
| 1321 | if (cc == 2) { |
| 1322 | bfsqueue[tail++] = yt*cr+xt; |
| 1323 | #ifdef STANDALONE_SOLVER |
| 1324 | bfsprev[yt*cr+xt] = yy*cr+xx; |
| 1325 | #endif |
| 1326 | number[yt*cr+xt] = tt - currn; |
| 1327 | } |
| 1328 | |
| 1329 | /* |
| 1330 | * One other possibility is that this |
| 1331 | * might be the square in which we can |
| 1332 | * make a real deduction: if it's |
| 1333 | * adjacent to x,y, and currn is equal |
| 1334 | * to the original number we ruled out. |
| 1335 | */ |
| 1336 | if (currn == orign && |
| 1337 | (xt == x || yt == y || |
| 1338 | (usage->blocks->whichblock[yt*cr+xt] == usage->blocks->whichblock[y*cr+x]) || |
| 1339 | (usage->diag && ((ondiag0(yt*cr+xt) && ondiag0(y*cr+x)) || |
| 1340 | (ondiag1(yt*cr+xt) && ondiag1(y*cr+x)))))) { |
| 1341 | #ifdef STANDALONE_SOLVER |
| 1342 | if (solver_show_working) { |
| 1343 | char *sep = ""; |
| 1344 | int xl, yl; |
| 1345 | printf("%*sforcing chain, %d at ends of ", |
| 1346 | solver_recurse_depth*4, "", orign); |
| 1347 | xl = xx; |
| 1348 | yl = yy; |
| 1349 | while (1) { |
| 1350 | printf("%s(%d,%d)", sep, 1+xl, |
| 1351 | 1+yl); |
| 1352 | xl = bfsprev[yl*cr+xl]; |
| 1353 | if (xl < 0) |
| 1354 | break; |
| 1355 | yl = xl / cr; |
| 1356 | xl %= cr; |
| 1357 | sep = "-"; |
| 1358 | } |
| 1359 | printf("\n%*s ruling out %d at (%d,%d)\n", |
| 1360 | solver_recurse_depth*4, "", |
| 1361 | orign, 1+xt, 1+yt); |
| 1362 | } |
| 1363 | #endif |
| 1364 | cube(xt, yt, orign) = FALSE; |
| 1365 | return 1; |
| 1366 | } |
| 1367 | } |
| 1368 | } |
| 1369 | } |
| 1370 | } |
| 1371 | |
| 1372 | return 0; |
| 1373 | } |
| 1374 | |
| 1375 | static int solver_killer_minmax(struct solver_usage *usage, |
| 1376 | struct block_structure *cages, digit *clues, |
| 1377 | int b |
| 1378 | #ifdef STANDALONE_SOLVER |
| 1379 | , const char *extra |
| 1380 | #endif |
| 1381 | ) |
| 1382 | { |
| 1383 | int cr = usage->cr; |
| 1384 | int i; |
| 1385 | int ret = 0; |
| 1386 | int nsquares = cages->nr_squares[b]; |
| 1387 | |
| 1388 | if (clues[b] == 0) |
| 1389 | return 0; |
| 1390 | |
| 1391 | for (i = 0; i < nsquares; i++) { |
| 1392 | int n, x = cages->blocks[b][i]; |
| 1393 | |
| 1394 | for (n = 1; n <= cr; n++) |
| 1395 | if (cube2(x, n)) { |
| 1396 | int maxval = 0, minval = 0; |
| 1397 | int j; |
| 1398 | for (j = 0; j < nsquares; j++) { |
| 1399 | int m; |
| 1400 | int y = cages->blocks[b][j]; |
| 1401 | if (i == j) |
| 1402 | continue; |
| 1403 | for (m = 1; m <= cr; m++) |
| 1404 | if (cube2(y, m)) { |
| 1405 | minval += m; |
| 1406 | break; |
| 1407 | } |
| 1408 | for (m = cr; m > 0; m--) |
| 1409 | if (cube2(y, m)) { |
| 1410 | maxval += m; |
| 1411 | break; |
| 1412 | } |
| 1413 | } |
| 1414 | if (maxval + n < clues[b]) { |
| 1415 | cube2(x, n) = FALSE; |
| 1416 | ret = 1; |
| 1417 | #ifdef STANDALONE_SOLVER |
| 1418 | if (solver_show_working) |
| 1419 | printf("%*s ruling out %d at (%d,%d) as too low %s\n", |
| 1420 | solver_recurse_depth*4, "killer minmax analysis", |
| 1421 | n, 1 + x%cr, 1 + x/cr, extra); |
| 1422 | #endif |
| 1423 | } |
| 1424 | if (minval + n > clues[b]) { |
| 1425 | cube2(x, n) = FALSE; |
| 1426 | ret = 1; |
| 1427 | #ifdef STANDALONE_SOLVER |
| 1428 | if (solver_show_working) |
| 1429 | printf("%*s ruling out %d at (%d,%d) as too high %s\n", |
| 1430 | solver_recurse_depth*4, "killer minmax analysis", |
| 1431 | n, 1 + x%cr, 1 + x/cr, extra); |
| 1432 | #endif |
| 1433 | } |
| 1434 | } |
| 1435 | } |
| 1436 | return ret; |
| 1437 | } |
| 1438 | |
| 1439 | static int solver_killer_sums(struct solver_usage *usage, int b, |
| 1440 | struct block_structure *cages, int clue, |
| 1441 | int cage_is_region |
| 1442 | #ifdef STANDALONE_SOLVER |
| 1443 | , const char *cage_type |
| 1444 | #endif |
| 1445 | ) |
| 1446 | { |
| 1447 | int cr = usage->cr; |
| 1448 | int i, ret, max_sums; |
| 1449 | int nsquares = cages->nr_squares[b]; |
| 1450 | unsigned long *sumbits, possible_addends; |
| 1451 | |
| 1452 | if (clue == 0) { |
| 1453 | assert(nsquares == 0); |
| 1454 | return 0; |
| 1455 | } |
| 1456 | assert(nsquares > 0); |
| 1457 | |
| 1458 | if (nsquares > 4) |
| 1459 | return 0; |
| 1460 | |
| 1461 | if (!cage_is_region) { |
| 1462 | int known_row = -1, known_col = -1, known_block = -1; |
| 1463 | /* |
| 1464 | * Verify that the cage lies entirely within one region, |
| 1465 | * so that using the precomputed sums is valid. |
| 1466 | */ |
| 1467 | for (i = 0; i < nsquares; i++) { |
| 1468 | int x = cages->blocks[b][i]; |
| 1469 | |
| 1470 | assert(usage->grid[x] == 0); |
| 1471 | |
| 1472 | if (i == 0) { |
| 1473 | known_row = x/cr; |
| 1474 | known_col = x%cr; |
| 1475 | known_block = usage->blocks->whichblock[x]; |
| 1476 | } else { |
| 1477 | if (known_row != x/cr) |
| 1478 | known_row = -1; |
| 1479 | if (known_col != x%cr) |
| 1480 | known_col = -1; |
| 1481 | if (known_block != usage->blocks->whichblock[x]) |
| 1482 | known_block = -1; |
| 1483 | } |
| 1484 | } |
| 1485 | if (known_block == -1 && known_col == -1 && known_row == -1) |
| 1486 | return 0; |
| 1487 | } |
| 1488 | if (nsquares == 2) { |
| 1489 | if (clue < 3 || clue > 17) |
| 1490 | return -1; |
| 1491 | |
| 1492 | sumbits = sum_bits2[clue]; |
| 1493 | max_sums = MAX_2SUMS; |
| 1494 | } else if (nsquares == 3) { |
| 1495 | if (clue < 6 || clue > 24) |
| 1496 | return -1; |
| 1497 | |
| 1498 | sumbits = sum_bits3[clue]; |
| 1499 | max_sums = MAX_3SUMS; |
| 1500 | } else { |
| 1501 | if (clue < 10 || clue > 30) |
| 1502 | return -1; |
| 1503 | |
| 1504 | sumbits = sum_bits4[clue]; |
| 1505 | max_sums = MAX_4SUMS; |
| 1506 | } |
| 1507 | /* |
| 1508 | * For every possible way to get the sum, see if there is |
| 1509 | * one square in the cage that disallows all the required |
| 1510 | * addends. If we find one such square, this way to compute |
| 1511 | * the sum is impossible. |
| 1512 | */ |
| 1513 | possible_addends = 0; |
| 1514 | for (i = 0; i < max_sums; i++) { |
| 1515 | int j; |
| 1516 | unsigned long bits = sumbits[i]; |
| 1517 | |
| 1518 | if (bits == 0) |
| 1519 | break; |
| 1520 | |
| 1521 | for (j = 0; j < nsquares; j++) { |
| 1522 | int n; |
| 1523 | unsigned long square_bits = bits; |
| 1524 | int x = cages->blocks[b][j]; |
| 1525 | for (n = 1; n <= cr; n++) |
| 1526 | if (!cube2(x, n)) |
| 1527 | square_bits &= ~(1L << n); |
| 1528 | if (square_bits == 0) { |
| 1529 | break; |
| 1530 | } |
| 1531 | } |
| 1532 | if (j == nsquares) |
| 1533 | possible_addends |= bits; |
| 1534 | } |
| 1535 | /* |
| 1536 | * Now we know which addends can possibly be used to |
| 1537 | * compute the sum. Remove all other digits from the |
| 1538 | * set of possibilities. |
| 1539 | */ |
| 1540 | if (possible_addends == 0) |
| 1541 | return -1; |
| 1542 | |
| 1543 | ret = 0; |
| 1544 | for (i = 0; i < nsquares; i++) { |
| 1545 | int n; |
| 1546 | int x = cages->blocks[b][i]; |
| 1547 | for (n = 1; n <= cr; n++) { |
| 1548 | if (!cube2(x, n)) |
| 1549 | continue; |
| 1550 | if ((possible_addends & (1 << n)) == 0) { |
| 1551 | cube2(x, n) = FALSE; |
| 1552 | ret = 1; |
| 1553 | #ifdef STANDALONE_SOLVER |
| 1554 | if (solver_show_working) { |
| 1555 | printf("%*s using %s\n", |
| 1556 | solver_recurse_depth*4, "killer sums analysis", |
| 1557 | cage_type); |
| 1558 | printf("%*s ruling out %d at (%d,%d) due to impossible %d-sum\n", |
| 1559 | solver_recurse_depth*4, "", |
| 1560 | n, 1 + x%cr, 1 + x/cr, nsquares); |
| 1561 | } |
| 1562 | #endif |
| 1563 | } |
| 1564 | } |
| 1565 | } |
| 1566 | return ret; |
| 1567 | } |
| 1568 | |
| 1569 | static int filter_whole_cages(struct solver_usage *usage, int *squares, int n, |
| 1570 | int *filtered_sum) |
| 1571 | { |
| 1572 | int b, i, j, off; |
| 1573 | *filtered_sum = 0; |
| 1574 | |
| 1575 | /* First, filter squares with a clue. */ |
| 1576 | for (i = j = 0; i < n; i++) |
| 1577 | if (usage->grid[squares[i]]) |
| 1578 | *filtered_sum += usage->grid[squares[i]]; |
| 1579 | else |
| 1580 | squares[j++] = squares[i]; |
| 1581 | n = j; |
| 1582 | |
| 1583 | /* |
| 1584 | * Filter all cages that are covered entirely by the list of |
| 1585 | * squares. |
| 1586 | */ |
| 1587 | off = 0; |
| 1588 | for (b = 0; b < usage->kblocks->nr_blocks && off < n; b++) { |
| 1589 | int b_squares = usage->kblocks->nr_squares[b]; |
| 1590 | int matched = 0; |
| 1591 | |
| 1592 | if (b_squares == 0) |
| 1593 | continue; |
| 1594 | |
| 1595 | /* |
| 1596 | * Find all squares of block b that lie in our list, |
| 1597 | * and make them contiguous at off, which is the current position |
| 1598 | * in the output list. |
| 1599 | */ |
| 1600 | for (i = 0; i < b_squares; i++) { |
| 1601 | for (j = off; j < n; j++) |
| 1602 | if (squares[j] == usage->kblocks->blocks[b][i]) { |
| 1603 | int t = squares[off + matched]; |
| 1604 | squares[off + matched] = squares[j]; |
| 1605 | squares[j] = t; |
| 1606 | matched++; |
| 1607 | break; |
| 1608 | } |
| 1609 | } |
| 1610 | /* If so, filter out all squares of b from the list. */ |
| 1611 | if (matched != usage->kblocks->nr_squares[b]) { |
| 1612 | off += matched; |
| 1613 | continue; |
| 1614 | } |
| 1615 | memmove(squares + off, squares + off + matched, |
| 1616 | (n - off - matched) * sizeof *squares); |
| 1617 | n -= matched; |
| 1618 | |
| 1619 | *filtered_sum += usage->kclues[b]; |
| 1620 | } |
| 1621 | assert(off == n); |
| 1622 | return off; |
| 1623 | } |
| 1624 | |
| 1625 | static struct solver_scratch *solver_new_scratch(struct solver_usage *usage) |
| 1626 | { |
| 1627 | struct solver_scratch *scratch = snew(struct solver_scratch); |
| 1628 | int cr = usage->cr; |
| 1629 | scratch->grid = snewn(cr*cr, unsigned char); |
| 1630 | scratch->rowidx = snewn(cr, unsigned char); |
| 1631 | scratch->colidx = snewn(cr, unsigned char); |
| 1632 | scratch->set = snewn(cr, unsigned char); |
| 1633 | scratch->neighbours = snewn(5*cr, int); |
| 1634 | scratch->bfsqueue = snewn(cr*cr, int); |
| 1635 | #ifdef STANDALONE_SOLVER |
| 1636 | scratch->bfsprev = snewn(cr*cr, int); |
| 1637 | #endif |
| 1638 | scratch->indexlist = snewn(cr*cr, int); /* used for set elimination */ |
| 1639 | scratch->indexlist2 = snewn(cr, int); /* only used for intersect() */ |
| 1640 | return scratch; |
| 1641 | } |
| 1642 | |
| 1643 | static void solver_free_scratch(struct solver_scratch *scratch) |
| 1644 | { |
| 1645 | #ifdef STANDALONE_SOLVER |
| 1646 | sfree(scratch->bfsprev); |
| 1647 | #endif |
| 1648 | sfree(scratch->bfsqueue); |
| 1649 | sfree(scratch->neighbours); |
| 1650 | sfree(scratch->set); |
| 1651 | sfree(scratch->colidx); |
| 1652 | sfree(scratch->rowidx); |
| 1653 | sfree(scratch->grid); |
| 1654 | sfree(scratch->indexlist); |
| 1655 | sfree(scratch->indexlist2); |
| 1656 | sfree(scratch); |
| 1657 | } |
| 1658 | |
| 1659 | /* |
| 1660 | * Used for passing information about difficulty levels between the solver |
| 1661 | * and its callers. |
| 1662 | */ |
| 1663 | struct difficulty { |
| 1664 | /* Maximum levels allowed. */ |
| 1665 | int maxdiff, maxkdiff; |
| 1666 | /* Levels reached by the solver. */ |
| 1667 | int diff, kdiff; |
| 1668 | }; |
| 1669 | |
| 1670 | static void solver(int cr, struct block_structure *blocks, |
| 1671 | struct block_structure *kblocks, int xtype, |
| 1672 | digit *grid, digit *kgrid, struct difficulty *dlev) |
| 1673 | { |
| 1674 | struct solver_usage *usage; |
| 1675 | struct solver_scratch *scratch; |
| 1676 | int x, y, b, i, n, ret; |
| 1677 | int diff = DIFF_BLOCK; |
| 1678 | int kdiff = DIFF_KSINGLE; |
| 1679 | |
| 1680 | /* |
| 1681 | * Set up a usage structure as a clean slate (everything |
| 1682 | * possible). |
| 1683 | */ |
| 1684 | usage = snew(struct solver_usage); |
| 1685 | usage->cr = cr; |
| 1686 | usage->blocks = blocks; |
| 1687 | if (kblocks) { |
| 1688 | usage->kblocks = dup_block_structure(kblocks); |
| 1689 | usage->extra_cages = alloc_block_structure (kblocks->c, kblocks->r, |
| 1690 | cr * cr, cr, cr * cr); |
| 1691 | usage->extra_clues = snewn(cr*cr, digit); |
| 1692 | } else { |
| 1693 | usage->kblocks = usage->extra_cages = NULL; |
| 1694 | usage->extra_clues = NULL; |
| 1695 | } |
| 1696 | usage->cube = snewn(cr*cr*cr, unsigned char); |
| 1697 | usage->grid = grid; /* write straight back to the input */ |
| 1698 | if (kgrid) { |
| 1699 | int nclues; |
| 1700 | |
| 1701 | assert(kblocks); |
| 1702 | nclues = kblocks->nr_blocks; |
| 1703 | /* |
| 1704 | * Allow for expansion of the killer regions, the absolute |
| 1705 | * limit is obviously one region per square. |
| 1706 | */ |
| 1707 | usage->kclues = snewn(cr*cr, digit); |
| 1708 | for (i = 0; i < nclues; i++) { |
| 1709 | for (n = 0; n < kblocks->nr_squares[i]; n++) |
| 1710 | if (kgrid[kblocks->blocks[i][n]] != 0) |
| 1711 | usage->kclues[i] = kgrid[kblocks->blocks[i][n]]; |
| 1712 | assert(usage->kclues[i] > 0); |
| 1713 | } |
| 1714 | memset(usage->kclues + nclues, 0, cr*cr - nclues); |
| 1715 | } else { |
| 1716 | usage->kclues = NULL; |
| 1717 | } |
| 1718 | |
| 1719 | memset(usage->cube, TRUE, cr*cr*cr); |
| 1720 | |
| 1721 | usage->row = snewn(cr * cr, unsigned char); |
| 1722 | usage->col = snewn(cr * cr, unsigned char); |
| 1723 | usage->blk = snewn(cr * cr, unsigned char); |
| 1724 | memset(usage->row, FALSE, cr * cr); |
| 1725 | memset(usage->col, FALSE, cr * cr); |
| 1726 | memset(usage->blk, FALSE, cr * cr); |
| 1727 | |
| 1728 | if (xtype) { |
| 1729 | usage->diag = snewn(cr * 2, unsigned char); |
| 1730 | memset(usage->diag, FALSE, cr * 2); |
| 1731 | } else |
| 1732 | usage->diag = NULL; |
| 1733 | |
| 1734 | usage->nr_regions = cr * 3 + (xtype ? 2 : 0); |
| 1735 | usage->regions = snewn(cr * usage->nr_regions, int); |
| 1736 | usage->sq2region = snewn(cr * cr * 3, int *); |
| 1737 | |
| 1738 | for (n = 0; n < cr; n++) { |
| 1739 | for (i = 0; i < cr; i++) { |
| 1740 | x = n*cr+i; |
| 1741 | y = i*cr+n; |
| 1742 | b = usage->blocks->blocks[n][i]; |
| 1743 | usage->regions[cr*n*3 + i] = x; |
| 1744 | usage->regions[cr*n*3 + cr + i] = y; |
| 1745 | usage->regions[cr*n*3 + 2*cr + i] = b; |
| 1746 | usage->sq2region[x*3] = usage->regions + cr*n*3; |
| 1747 | usage->sq2region[y*3 + 1] = usage->regions + cr*n*3 + cr; |
| 1748 | usage->sq2region[b*3 + 2] = usage->regions + cr*n*3 + 2*cr; |
| 1749 | } |
| 1750 | } |
| 1751 | |
| 1752 | scratch = solver_new_scratch(usage); |
| 1753 | |
| 1754 | /* |
| 1755 | * Place all the clue numbers we are given. |
| 1756 | */ |
| 1757 | for (x = 0; x < cr; x++) |
| 1758 | for (y = 0; y < cr; y++) |
| 1759 | if (grid[y*cr+x]) |
| 1760 | solver_place(usage, x, y, grid[y*cr+x]); |
| 1761 | |
| 1762 | /* |
| 1763 | * Now loop over the grid repeatedly trying all permitted modes |
| 1764 | * of reasoning. The loop terminates if we complete an |
| 1765 | * iteration without making any progress; we then return |
| 1766 | * failure or success depending on whether the grid is full or |
| 1767 | * not. |
| 1768 | */ |
| 1769 | while (1) { |
| 1770 | /* |
| 1771 | * I'd like to write `continue;' inside each of the |
| 1772 | * following loops, so that the solver returns here after |
| 1773 | * making some progress. However, I can't specify that I |
| 1774 | * want to continue an outer loop rather than the innermost |
| 1775 | * one, so I'm apologetically resorting to a goto. |
| 1776 | */ |
| 1777 | cont: |
| 1778 | |
| 1779 | /* |
| 1780 | * Blockwise positional elimination. |
| 1781 | */ |
| 1782 | for (b = 0; b < cr; b++) |
| 1783 | for (n = 1; n <= cr; n++) |
| 1784 | if (!usage->blk[b*cr+n-1]) { |
| 1785 | for (i = 0; i < cr; i++) |
| 1786 | scratch->indexlist[i] = cubepos2(usage->blocks->blocks[b][i],n); |
| 1787 | ret = solver_elim(usage, scratch->indexlist |
| 1788 | #ifdef STANDALONE_SOLVER |
| 1789 | , "positional elimination," |
| 1790 | " %d in block %s", n, |
| 1791 | usage->blocks->blocknames[b] |
| 1792 | #endif |
| 1793 | ); |
| 1794 | if (ret < 0) { |
| 1795 | diff = DIFF_IMPOSSIBLE; |
| 1796 | goto got_result; |
| 1797 | } else if (ret > 0) { |
| 1798 | diff = max(diff, DIFF_BLOCK); |
| 1799 | goto cont; |
| 1800 | } |
| 1801 | } |
| 1802 | |
| 1803 | if (usage->kclues != NULL) { |
| 1804 | int changed = FALSE; |
| 1805 | |
| 1806 | /* |
| 1807 | * First, bring the kblocks into a more useful form: remove |
| 1808 | * all filled-in squares, and reduce the sum by their values. |
| 1809 | * Walk in reverse order, since otherwise remove_from_block |
| 1810 | * can move element past our loop counter. |
| 1811 | */ |
| 1812 | for (b = 0; b < usage->kblocks->nr_blocks; b++) |
| 1813 | for (i = usage->kblocks->nr_squares[b] -1; i >= 0; i--) { |
| 1814 | int x = usage->kblocks->blocks[b][i]; |
| 1815 | int t = usage->grid[x]; |
| 1816 | |
| 1817 | if (t == 0) |
| 1818 | continue; |
| 1819 | remove_from_block(usage->kblocks, b, x); |
| 1820 | if (t > usage->kclues[b]) { |
| 1821 | diff = DIFF_IMPOSSIBLE; |
| 1822 | goto got_result; |
| 1823 | } |
| 1824 | usage->kclues[b] -= t; |
| 1825 | /* |
| 1826 | * Since cages are regions, this tells us something |
| 1827 | * about the other squares in the cage. |
| 1828 | */ |
| 1829 | for (n = 0; n < usage->kblocks->nr_squares[b]; n++) { |
| 1830 | cube2(usage->kblocks->blocks[b][n], t) = FALSE; |
| 1831 | } |
| 1832 | } |
| 1833 | |
| 1834 | /* |
| 1835 | * The most trivial kind of solver for killer puzzles: fill |
| 1836 | * single-square cages. |
| 1837 | */ |
| 1838 | for (b = 0; b < usage->kblocks->nr_blocks; b++) { |
| 1839 | int squares = usage->kblocks->nr_squares[b]; |
| 1840 | if (squares == 1) { |
| 1841 | int v = usage->kclues[b]; |
| 1842 | if (v < 1 || v > cr) { |
| 1843 | diff = DIFF_IMPOSSIBLE; |
| 1844 | goto got_result; |
| 1845 | } |
| 1846 | x = usage->kblocks->blocks[b][0] % cr; |
| 1847 | y = usage->kblocks->blocks[b][0] / cr; |
| 1848 | if (!cube(x, y, v)) { |
| 1849 | diff = DIFF_IMPOSSIBLE; |
| 1850 | goto got_result; |
| 1851 | } |
| 1852 | solver_place(usage, x, y, v); |
| 1853 | |
| 1854 | #ifdef STANDALONE_SOLVER |
| 1855 | if (solver_show_working) { |
| 1856 | printf("%*s placing %d at (%d,%d)\n", |
| 1857 | solver_recurse_depth*4, "killer single-square cage", |
| 1858 | v, 1 + x%cr, 1 + x/cr); |
| 1859 | } |
| 1860 | #endif |
| 1861 | changed = TRUE; |
| 1862 | } |
| 1863 | } |
| 1864 | |
| 1865 | if (changed) { |
| 1866 | kdiff = max(kdiff, DIFF_KSINGLE); |
| 1867 | goto cont; |
| 1868 | } |
| 1869 | } |
| 1870 | if (dlev->maxkdiff >= DIFF_KINTERSECT && usage->kclues != NULL) { |
| 1871 | int changed = FALSE; |
| 1872 | /* |
| 1873 | * Now, create the extra_cages information. Every full region |
| 1874 | * (row, column, or block) has the same sum total (45 for 3x3 |
| 1875 | * puzzles. After we try to cover these regions with cages that |
| 1876 | * lie entirely within them, any squares that remain must bring |
| 1877 | * the total to this known value, and so they form additional |
| 1878 | * cages which aren't immediately evident in the displayed form |
| 1879 | * of the puzzle. |
| 1880 | */ |
| 1881 | usage->extra_cages->nr_blocks = 0; |
| 1882 | for (i = 0; i < 3; i++) { |
| 1883 | for (n = 0; n < cr; n++) { |
| 1884 | int *region = usage->regions + cr*n*3 + i*cr; |
| 1885 | int sum = cr * (cr + 1) / 2; |
| 1886 | int nsquares = cr; |
| 1887 | int filtered; |
| 1888 | int n_extra = usage->extra_cages->nr_blocks; |
| 1889 | int *extra_list = usage->extra_cages->blocks[n_extra]; |
| 1890 | memcpy(extra_list, region, cr * sizeof *extra_list); |
| 1891 | |
| 1892 | nsquares = filter_whole_cages(usage, extra_list, nsquares, &filtered); |
| 1893 | sum -= filtered; |
| 1894 | if (nsquares == cr || nsquares == 0) |
| 1895 | continue; |
| 1896 | if (dlev->maxdiff >= DIFF_RECURSIVE) { |
| 1897 | if (sum <= 0) { |
| 1898 | dlev->diff = DIFF_IMPOSSIBLE; |
| 1899 | goto got_result; |
| 1900 | } |
| 1901 | } |
| 1902 | assert(sum > 0); |
| 1903 | |
| 1904 | if (nsquares == 1) { |
| 1905 | if (sum > cr) { |
| 1906 | diff = DIFF_IMPOSSIBLE; |
| 1907 | goto got_result; |
| 1908 | } |
| 1909 | x = extra_list[0] % cr; |
| 1910 | y = extra_list[0] / cr; |
| 1911 | if (!cube(x, y, sum)) { |
| 1912 | diff = DIFF_IMPOSSIBLE; |
| 1913 | goto got_result; |
| 1914 | } |
| 1915 | solver_place(usage, x, y, sum); |
| 1916 | changed = TRUE; |
| 1917 | #ifdef STANDALONE_SOLVER |
| 1918 | if (solver_show_working) { |
| 1919 | printf("%*s placing %d at (%d,%d)\n", |
| 1920 | solver_recurse_depth*4, "killer single-square deduced cage", |
| 1921 | sum, 1 + x, 1 + y); |
| 1922 | } |
| 1923 | #endif |
| 1924 | } |
| 1925 | |
| 1926 | b = usage->kblocks->whichblock[extra_list[0]]; |
| 1927 | for (x = 1; x < nsquares; x++) |
| 1928 | if (usage->kblocks->whichblock[extra_list[x]] != b) |
| 1929 | break; |
| 1930 | if (x == nsquares) { |
| 1931 | assert(usage->kblocks->nr_squares[b] > nsquares); |
| 1932 | split_block(usage->kblocks, extra_list, nsquares); |
| 1933 | assert(usage->kblocks->nr_squares[usage->kblocks->nr_blocks - 1] == nsquares); |
| 1934 | usage->kclues[usage->kblocks->nr_blocks - 1] = sum; |
| 1935 | usage->kclues[b] -= sum; |
| 1936 | } else { |
| 1937 | usage->extra_cages->nr_squares[n_extra] = nsquares; |
| 1938 | usage->extra_cages->nr_blocks++; |
| 1939 | usage->extra_clues[n_extra] = sum; |
| 1940 | } |
| 1941 | } |
| 1942 | } |
| 1943 | if (changed) { |
| 1944 | kdiff = max(kdiff, DIFF_KINTERSECT); |
| 1945 | goto cont; |
| 1946 | } |
| 1947 | } |
| 1948 | |
| 1949 | /* |
| 1950 | * Another simple killer-type elimination. For every square in a |
| 1951 | * cage, find the minimum and maximum possible sums of all the |
| 1952 | * other squares in the same cage, and rule out possibilities |
| 1953 | * for the given square based on whether they are guaranteed to |
| 1954 | * cause the sum to be either too high or too low. |
| 1955 | * This is a special case of trying all possible sums across a |
| 1956 | * region, which is a recursive algorithm. We should probably |
| 1957 | * implement it for a higher difficulty level. |
| 1958 | */ |
| 1959 | if (dlev->maxkdiff >= DIFF_KMINMAX && usage->kclues != NULL) { |
| 1960 | int changed = FALSE; |
| 1961 | for (b = 0; b < usage->kblocks->nr_blocks; b++) { |
| 1962 | int ret = solver_killer_minmax(usage, usage->kblocks, |
| 1963 | usage->kclues, b |
| 1964 | #ifdef STANDALONE_SOLVER |
| 1965 | , "" |
| 1966 | #endif |
| 1967 | ); |
| 1968 | if (ret < 0) { |
| 1969 | diff = DIFF_IMPOSSIBLE; |
| 1970 | goto got_result; |
| 1971 | } else if (ret > 0) |
| 1972 | changed = TRUE; |
| 1973 | } |
| 1974 | for (b = 0; b < usage->extra_cages->nr_blocks; b++) { |
| 1975 | int ret = solver_killer_minmax(usage, usage->extra_cages, |
| 1976 | usage->extra_clues, b |
| 1977 | #ifdef STANDALONE_SOLVER |
| 1978 | , "using deduced cages" |
| 1979 | #endif |
| 1980 | ); |
| 1981 | if (ret < 0) { |
| 1982 | diff = DIFF_IMPOSSIBLE; |
| 1983 | goto got_result; |
| 1984 | } else if (ret > 0) |
| 1985 | changed = TRUE; |
| 1986 | } |
| 1987 | if (changed) { |
| 1988 | kdiff = max(kdiff, DIFF_KMINMAX); |
| 1989 | goto cont; |
| 1990 | } |
| 1991 | } |
| 1992 | |
| 1993 | /* |
| 1994 | * Try to use knowledge of which numbers can be used to generate |
| 1995 | * a given sum. |
| 1996 | * This can only be used if a cage lies entirely within a region. |
| 1997 | */ |
| 1998 | if (dlev->maxkdiff >= DIFF_KSUMS && usage->kclues != NULL) { |
| 1999 | int changed = FALSE; |
| 2000 | |
| 2001 | for (b = 0; b < usage->kblocks->nr_blocks; b++) { |
| 2002 | int ret = solver_killer_sums(usage, b, usage->kblocks, |
| 2003 | usage->kclues[b], TRUE |
| 2004 | #ifdef STANDALONE_SOLVER |
| 2005 | , "regular clues" |
| 2006 | #endif |
| 2007 | ); |
| 2008 | if (ret > 0) { |
| 2009 | changed = TRUE; |
| 2010 | kdiff = max(kdiff, DIFF_KSUMS); |
| 2011 | } else if (ret < 0) { |
| 2012 | diff = DIFF_IMPOSSIBLE; |
| 2013 | goto got_result; |
| 2014 | } |
| 2015 | } |
| 2016 | |
| 2017 | for (b = 0; b < usage->extra_cages->nr_blocks; b++) { |
| 2018 | int ret = solver_killer_sums(usage, b, usage->extra_cages, |
| 2019 | usage->extra_clues[b], FALSE |
| 2020 | #ifdef STANDALONE_SOLVER |
| 2021 | , "deduced clues" |
| 2022 | #endif |
| 2023 | ); |
| 2024 | if (ret > 0) { |
| 2025 | changed = TRUE; |
| 2026 | kdiff = max(kdiff, DIFF_KINTERSECT); |
| 2027 | } else if (ret < 0) { |
| 2028 | diff = DIFF_IMPOSSIBLE; |
| 2029 | goto got_result; |
| 2030 | } |
| 2031 | } |
| 2032 | |
| 2033 | if (changed) |
| 2034 | goto cont; |
| 2035 | } |
| 2036 | |
| 2037 | if (dlev->maxdiff <= DIFF_BLOCK) |
| 2038 | break; |
| 2039 | |
| 2040 | /* |
| 2041 | * Row-wise positional elimination. |
| 2042 | */ |
| 2043 | for (y = 0; y < cr; y++) |
| 2044 | for (n = 1; n <= cr; n++) |
| 2045 | if (!usage->row[y*cr+n-1]) { |
| 2046 | for (x = 0; x < cr; x++) |
| 2047 | scratch->indexlist[x] = cubepos(x, y, n); |
| 2048 | ret = solver_elim(usage, scratch->indexlist |
| 2049 | #ifdef STANDALONE_SOLVER |
| 2050 | , "positional elimination," |
| 2051 | " %d in row %d", n, 1+y |
| 2052 | #endif |
| 2053 | ); |
| 2054 | if (ret < 0) { |
| 2055 | diff = DIFF_IMPOSSIBLE; |
| 2056 | goto got_result; |
| 2057 | } else if (ret > 0) { |
| 2058 | diff = max(diff, DIFF_SIMPLE); |
| 2059 | goto cont; |
| 2060 | } |
| 2061 | } |
| 2062 | /* |
| 2063 | * Column-wise positional elimination. |
| 2064 | */ |
| 2065 | for (x = 0; x < cr; x++) |
| 2066 | for (n = 1; n <= cr; n++) |
| 2067 | if (!usage->col[x*cr+n-1]) { |
| 2068 | for (y = 0; y < cr; y++) |
| 2069 | scratch->indexlist[y] = cubepos(x, y, n); |
| 2070 | ret = solver_elim(usage, scratch->indexlist |
| 2071 | #ifdef STANDALONE_SOLVER |
| 2072 | , "positional elimination," |
| 2073 | " %d in column %d", n, 1+x |
| 2074 | #endif |
| 2075 | ); |
| 2076 | if (ret < 0) { |
| 2077 | diff = DIFF_IMPOSSIBLE; |
| 2078 | goto got_result; |
| 2079 | } else if (ret > 0) { |
| 2080 | diff = max(diff, DIFF_SIMPLE); |
| 2081 | goto cont; |
| 2082 | } |
| 2083 | } |
| 2084 | |
| 2085 | /* |
| 2086 | * X-diagonal positional elimination. |
| 2087 | */ |
| 2088 | if (usage->diag) { |
| 2089 | for (n = 1; n <= cr; n++) |
| 2090 | if (!usage->diag[n-1]) { |
| 2091 | for (i = 0; i < cr; i++) |
| 2092 | scratch->indexlist[i] = cubepos2(diag0(i), n); |
| 2093 | ret = solver_elim(usage, scratch->indexlist |
| 2094 | #ifdef STANDALONE_SOLVER |
| 2095 | , "positional elimination," |
| 2096 | " %d in \\-diagonal", n |
| 2097 | #endif |
| 2098 | ); |
| 2099 | if (ret < 0) { |
| 2100 | diff = DIFF_IMPOSSIBLE; |
| 2101 | goto got_result; |
| 2102 | } else if (ret > 0) { |
| 2103 | diff = max(diff, DIFF_SIMPLE); |
| 2104 | goto cont; |
| 2105 | } |
| 2106 | } |
| 2107 | for (n = 1; n <= cr; n++) |
| 2108 | if (!usage->diag[cr+n-1]) { |
| 2109 | for (i = 0; i < cr; i++) |
| 2110 | scratch->indexlist[i] = cubepos2(diag1(i), n); |
| 2111 | ret = solver_elim(usage, scratch->indexlist |
| 2112 | #ifdef STANDALONE_SOLVER |
| 2113 | , "positional elimination," |
| 2114 | " %d in /-diagonal", n |
| 2115 | #endif |
| 2116 | ); |
| 2117 | if (ret < 0) { |
| 2118 | diff = DIFF_IMPOSSIBLE; |
| 2119 | goto got_result; |
| 2120 | } else if (ret > 0) { |
| 2121 | diff = max(diff, DIFF_SIMPLE); |
| 2122 | goto cont; |
| 2123 | } |
| 2124 | } |
| 2125 | } |
| 2126 | |
| 2127 | /* |
| 2128 | * Numeric elimination. |
| 2129 | */ |
| 2130 | for (x = 0; x < cr; x++) |
| 2131 | for (y = 0; y < cr; y++) |
| 2132 | if (!usage->grid[y*cr+x]) { |
| 2133 | for (n = 1; n <= cr; n++) |
| 2134 | scratch->indexlist[n-1] = cubepos(x, y, n); |
| 2135 | ret = solver_elim(usage, scratch->indexlist |
| 2136 | #ifdef STANDALONE_SOLVER |
| 2137 | , "numeric elimination at (%d,%d)", |
| 2138 | 1+x, 1+y |
| 2139 | #endif |
| 2140 | ); |
| 2141 | if (ret < 0) { |
| 2142 | diff = DIFF_IMPOSSIBLE; |
| 2143 | goto got_result; |
| 2144 | } else if (ret > 0) { |
| 2145 | diff = max(diff, DIFF_SIMPLE); |
| 2146 | goto cont; |
| 2147 | } |
| 2148 | } |
| 2149 | |
| 2150 | if (dlev->maxdiff <= DIFF_SIMPLE) |
| 2151 | break; |
| 2152 | |
| 2153 | /* |
| 2154 | * Intersectional analysis, rows vs blocks. |
| 2155 | */ |
| 2156 | for (y = 0; y < cr; y++) |
| 2157 | for (b = 0; b < cr; b++) |
| 2158 | for (n = 1; n <= cr; n++) { |
| 2159 | if (usage->row[y*cr+n-1] || |
| 2160 | usage->blk[b*cr+n-1]) |
| 2161 | continue; |
| 2162 | for (i = 0; i < cr; i++) { |
| 2163 | scratch->indexlist[i] = cubepos(i, y, n); |
| 2164 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
| 2165 | } |
| 2166 | /* |
| 2167 | * solver_intersect() never returns -1. |
| 2168 | */ |
| 2169 | if (solver_intersect(usage, scratch->indexlist, |
| 2170 | scratch->indexlist2 |
| 2171 | #ifdef STANDALONE_SOLVER |
| 2172 | , "intersectional analysis," |
| 2173 | " %d in row %d vs block %s", |
| 2174 | n, 1+y, usage->blocks->blocknames[b] |
| 2175 | #endif |
| 2176 | ) || |
| 2177 | solver_intersect(usage, scratch->indexlist2, |
| 2178 | scratch->indexlist |
| 2179 | #ifdef STANDALONE_SOLVER |
| 2180 | , "intersectional analysis," |
| 2181 | " %d in block %s vs row %d", |
| 2182 | n, usage->blocks->blocknames[b], 1+y |
| 2183 | #endif |
| 2184 | )) { |
| 2185 | diff = max(diff, DIFF_INTERSECT); |
| 2186 | goto cont; |
| 2187 | } |
| 2188 | } |
| 2189 | |
| 2190 | /* |
| 2191 | * Intersectional analysis, columns vs blocks. |
| 2192 | */ |
| 2193 | for (x = 0; x < cr; x++) |
| 2194 | for (b = 0; b < cr; b++) |
| 2195 | for (n = 1; n <= cr; n++) { |
| 2196 | if (usage->col[x*cr+n-1] || |
| 2197 | usage->blk[b*cr+n-1]) |
| 2198 | continue; |
| 2199 | for (i = 0; i < cr; i++) { |
| 2200 | scratch->indexlist[i] = cubepos(x, i, n); |
| 2201 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
| 2202 | } |
| 2203 | if (solver_intersect(usage, scratch->indexlist, |
| 2204 | scratch->indexlist2 |
| 2205 | #ifdef STANDALONE_SOLVER |
| 2206 | , "intersectional analysis," |
| 2207 | " %d in column %d vs block %s", |
| 2208 | n, 1+x, usage->blocks->blocknames[b] |
| 2209 | #endif |
| 2210 | ) || |
| 2211 | solver_intersect(usage, scratch->indexlist2, |
| 2212 | scratch->indexlist |
| 2213 | #ifdef STANDALONE_SOLVER |
| 2214 | , "intersectional analysis," |
| 2215 | " %d in block %s vs column %d", |
| 2216 | n, usage->blocks->blocknames[b], 1+x |
| 2217 | #endif |
| 2218 | )) { |
| 2219 | diff = max(diff, DIFF_INTERSECT); |
| 2220 | goto cont; |
| 2221 | } |
| 2222 | } |
| 2223 | |
| 2224 | if (usage->diag) { |
| 2225 | /* |
| 2226 | * Intersectional analysis, \-diagonal vs blocks. |
| 2227 | */ |
| 2228 | for (b = 0; b < cr; b++) |
| 2229 | for (n = 1; n <= cr; n++) { |
| 2230 | if (usage->diag[n-1] || |
| 2231 | usage->blk[b*cr+n-1]) |
| 2232 | continue; |
| 2233 | for (i = 0; i < cr; i++) { |
| 2234 | scratch->indexlist[i] = cubepos2(diag0(i), n); |
| 2235 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
| 2236 | } |
| 2237 | if (solver_intersect(usage, scratch->indexlist, |
| 2238 | scratch->indexlist2 |
| 2239 | #ifdef STANDALONE_SOLVER |
| 2240 | , "intersectional analysis," |
| 2241 | " %d in \\-diagonal vs block %s", |
| 2242 | n, 1+x, usage->blocks->blocknames[b] |
| 2243 | #endif |
| 2244 | ) || |
| 2245 | solver_intersect(usage, scratch->indexlist2, |
| 2246 | scratch->indexlist |
| 2247 | #ifdef STANDALONE_SOLVER |
| 2248 | , "intersectional analysis," |
| 2249 | " %d in block %s vs \\-diagonal", |
| 2250 | n, usage->blocks->blocknames[b], 1+x |
| 2251 | #endif |
| 2252 | )) { |
| 2253 | diff = max(diff, DIFF_INTERSECT); |
| 2254 | goto cont; |
| 2255 | } |
| 2256 | } |
| 2257 | |
| 2258 | /* |
| 2259 | * Intersectional analysis, /-diagonal vs blocks. |
| 2260 | */ |
| 2261 | for (b = 0; b < cr; b++) |
| 2262 | for (n = 1; n <= cr; n++) { |
| 2263 | if (usage->diag[cr+n-1] || |
| 2264 | usage->blk[b*cr+n-1]) |
| 2265 | continue; |
| 2266 | for (i = 0; i < cr; i++) { |
| 2267 | scratch->indexlist[i] = cubepos2(diag1(i), n); |
| 2268 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
| 2269 | } |
| 2270 | if (solver_intersect(usage, scratch->indexlist, |
| 2271 | scratch->indexlist2 |
| 2272 | #ifdef STANDALONE_SOLVER |
| 2273 | , "intersectional analysis," |
| 2274 | " %d in /-diagonal vs block %s", |
| 2275 | n, 1+x, usage->blocks->blocknames[b] |
| 2276 | #endif |
| 2277 | ) || |
| 2278 | solver_intersect(usage, scratch->indexlist2, |
| 2279 | scratch->indexlist |
| 2280 | #ifdef STANDALONE_SOLVER |
| 2281 | , "intersectional analysis," |
| 2282 | " %d in block %s vs /-diagonal", |
| 2283 | n, usage->blocks->blocknames[b], 1+x |
| 2284 | #endif |
| 2285 | )) { |
| 2286 | diff = max(diff, DIFF_INTERSECT); |
| 2287 | goto cont; |
| 2288 | } |
| 2289 | } |
| 2290 | } |
| 2291 | |
| 2292 | if (dlev->maxdiff <= DIFF_INTERSECT) |
| 2293 | break; |
| 2294 | |
| 2295 | /* |
| 2296 | * Blockwise set elimination. |
| 2297 | */ |
| 2298 | for (b = 0; b < cr; b++) { |
| 2299 | for (i = 0; i < cr; i++) |
| 2300 | for (n = 1; n <= cr; n++) |
| 2301 | scratch->indexlist[i*cr+n-1] = cubepos2(usage->blocks->blocks[b][i], n); |
| 2302 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2303 | #ifdef STANDALONE_SOLVER |
| 2304 | , "set elimination, block %s", |
| 2305 | usage->blocks->blocknames[b] |
| 2306 | #endif |
| 2307 | ); |
| 2308 | if (ret < 0) { |
| 2309 | diff = DIFF_IMPOSSIBLE; |
| 2310 | goto got_result; |
| 2311 | } else if (ret > 0) { |
| 2312 | diff = max(diff, DIFF_SET); |
| 2313 | goto cont; |
| 2314 | } |
| 2315 | } |
| 2316 | |
| 2317 | /* |
| 2318 | * Row-wise set elimination. |
| 2319 | */ |
| 2320 | for (y = 0; y < cr; y++) { |
| 2321 | for (x = 0; x < cr; x++) |
| 2322 | for (n = 1; n <= cr; n++) |
| 2323 | scratch->indexlist[x*cr+n-1] = cubepos(x, y, n); |
| 2324 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2325 | #ifdef STANDALONE_SOLVER |
| 2326 | , "set elimination, row %d", 1+y |
| 2327 | #endif |
| 2328 | ); |
| 2329 | if (ret < 0) { |
| 2330 | diff = DIFF_IMPOSSIBLE; |
| 2331 | goto got_result; |
| 2332 | } else if (ret > 0) { |
| 2333 | diff = max(diff, DIFF_SET); |
| 2334 | goto cont; |
| 2335 | } |
| 2336 | } |
| 2337 | |
| 2338 | /* |
| 2339 | * Column-wise set elimination. |
| 2340 | */ |
| 2341 | for (x = 0; x < cr; x++) { |
| 2342 | for (y = 0; y < cr; y++) |
| 2343 | for (n = 1; n <= cr; n++) |
| 2344 | scratch->indexlist[y*cr+n-1] = cubepos(x, y, n); |
| 2345 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2346 | #ifdef STANDALONE_SOLVER |
| 2347 | , "set elimination, column %d", 1+x |
| 2348 | #endif |
| 2349 | ); |
| 2350 | if (ret < 0) { |
| 2351 | diff = DIFF_IMPOSSIBLE; |
| 2352 | goto got_result; |
| 2353 | } else if (ret > 0) { |
| 2354 | diff = max(diff, DIFF_SET); |
| 2355 | goto cont; |
| 2356 | } |
| 2357 | } |
| 2358 | |
| 2359 | if (usage->diag) { |
| 2360 | /* |
| 2361 | * \-diagonal set elimination. |
| 2362 | */ |
| 2363 | for (i = 0; i < cr; i++) |
| 2364 | for (n = 1; n <= cr; n++) |
| 2365 | scratch->indexlist[i*cr+n-1] = cubepos2(diag0(i), n); |
| 2366 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2367 | #ifdef STANDALONE_SOLVER |
| 2368 | , "set elimination, \\-diagonal" |
| 2369 | #endif |
| 2370 | ); |
| 2371 | if (ret < 0) { |
| 2372 | diff = DIFF_IMPOSSIBLE; |
| 2373 | goto got_result; |
| 2374 | } else if (ret > 0) { |
| 2375 | diff = max(diff, DIFF_SET); |
| 2376 | goto cont; |
| 2377 | } |
| 2378 | |
| 2379 | /* |
| 2380 | * /-diagonal set elimination. |
| 2381 | */ |
| 2382 | for (i = 0; i < cr; i++) |
| 2383 | for (n = 1; n <= cr; n++) |
| 2384 | scratch->indexlist[i*cr+n-1] = cubepos2(diag1(i), n); |
| 2385 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2386 | #ifdef STANDALONE_SOLVER |
| 2387 | , "set elimination, \\-diagonal" |
| 2388 | #endif |
| 2389 | ); |
| 2390 | if (ret < 0) { |
| 2391 | diff = DIFF_IMPOSSIBLE; |
| 2392 | goto got_result; |
| 2393 | } else if (ret > 0) { |
| 2394 | diff = max(diff, DIFF_SET); |
| 2395 | goto cont; |
| 2396 | } |
| 2397 | } |
| 2398 | |
| 2399 | if (dlev->maxdiff <= DIFF_SET) |
| 2400 | break; |
| 2401 | |
| 2402 | /* |
| 2403 | * Row-vs-column set elimination on a single number. |
| 2404 | */ |
| 2405 | for (n = 1; n <= cr; n++) { |
| 2406 | for (y = 0; y < cr; y++) |
| 2407 | for (x = 0; x < cr; x++) |
| 2408 | scratch->indexlist[y*cr+x] = cubepos(x, y, n); |
| 2409 | ret = solver_set(usage, scratch, scratch->indexlist |
| 2410 | #ifdef STANDALONE_SOLVER |
| 2411 | , "positional set elimination, number %d", n |
| 2412 | #endif |
| 2413 | ); |
| 2414 | if (ret < 0) { |
| 2415 | diff = DIFF_IMPOSSIBLE; |
| 2416 | goto got_result; |
| 2417 | } else if (ret > 0) { |
| 2418 | diff = max(diff, DIFF_EXTREME); |
| 2419 | goto cont; |
| 2420 | } |
| 2421 | } |
| 2422 | |
| 2423 | /* |
| 2424 | * Forcing chains. |
| 2425 | */ |
| 2426 | if (solver_forcing(usage, scratch)) { |
| 2427 | diff = max(diff, DIFF_EXTREME); |
| 2428 | goto cont; |
| 2429 | } |
| 2430 | |
| 2431 | /* |
| 2432 | * If we reach here, we have made no deductions in this |
| 2433 | * iteration, so the algorithm terminates. |
| 2434 | */ |
| 2435 | break; |
| 2436 | } |
| 2437 | |
| 2438 | /* |
| 2439 | * Last chance: if we haven't fully solved the puzzle yet, try |
| 2440 | * recursing based on guesses for a particular square. We pick |
| 2441 | * one of the most constrained empty squares we can find, which |
| 2442 | * has the effect of pruning the search tree as much as |
| 2443 | * possible. |
| 2444 | */ |
| 2445 | if (dlev->maxdiff >= DIFF_RECURSIVE) { |
| 2446 | int best, bestcount; |
| 2447 | |
| 2448 | best = -1; |
| 2449 | bestcount = cr+1; |
| 2450 | |
| 2451 | for (y = 0; y < cr; y++) |
| 2452 | for (x = 0; x < cr; x++) |
| 2453 | if (!grid[y*cr+x]) { |
| 2454 | int count; |
| 2455 | |
| 2456 | /* |
| 2457 | * An unfilled square. Count the number of |
| 2458 | * possible digits in it. |
| 2459 | */ |
| 2460 | count = 0; |
| 2461 | for (n = 1; n <= cr; n++) |
| 2462 | if (cube(x,y,n)) |
| 2463 | count++; |
| 2464 | |
| 2465 | /* |
| 2466 | * We should have found any impossibilities |
| 2467 | * already, so this can safely be an assert. |
| 2468 | */ |
| 2469 | assert(count > 1); |
| 2470 | |
| 2471 | if (count < bestcount) { |
| 2472 | bestcount = count; |
| 2473 | best = y*cr+x; |
| 2474 | } |
| 2475 | } |
| 2476 | |
| 2477 | if (best != -1) { |
| 2478 | int i, j; |
| 2479 | digit *list, *ingrid, *outgrid; |
| 2480 | |
| 2481 | diff = DIFF_IMPOSSIBLE; /* no solution found yet */ |
| 2482 | |
| 2483 | /* |
| 2484 | * Attempt recursion. |
| 2485 | */ |
| 2486 | y = best / cr; |
| 2487 | x = best % cr; |
| 2488 | |
| 2489 | list = snewn(cr, digit); |
| 2490 | ingrid = snewn(cr * cr, digit); |
| 2491 | outgrid = snewn(cr * cr, digit); |
| 2492 | memcpy(ingrid, grid, cr * cr); |
| 2493 | |
| 2494 | /* Make a list of the possible digits. */ |
| 2495 | for (j = 0, n = 1; n <= cr; n++) |
| 2496 | if (cube(x,y,n)) |
| 2497 | list[j++] = n; |
| 2498 | |
| 2499 | #ifdef STANDALONE_SOLVER |
| 2500 | if (solver_show_working) { |
| 2501 | char *sep = ""; |
| 2502 | printf("%*srecursing on (%d,%d) [", |
| 2503 | solver_recurse_depth*4, "", x + 1, y + 1); |
| 2504 | for (i = 0; i < j; i++) { |
| 2505 | printf("%s%d", sep, list[i]); |
| 2506 | sep = " or "; |
| 2507 | } |
| 2508 | printf("]\n"); |
| 2509 | } |
| 2510 | #endif |
| 2511 | |
| 2512 | /* |
| 2513 | * And step along the list, recursing back into the |
| 2514 | * main solver at every stage. |
| 2515 | */ |
| 2516 | for (i = 0; i < j; i++) { |
| 2517 | memcpy(outgrid, ingrid, cr * cr); |
| 2518 | outgrid[y*cr+x] = list[i]; |
| 2519 | |
| 2520 | #ifdef STANDALONE_SOLVER |
| 2521 | if (solver_show_working) |
| 2522 | printf("%*sguessing %d at (%d,%d)\n", |
| 2523 | solver_recurse_depth*4, "", list[i], x + 1, y + 1); |
| 2524 | solver_recurse_depth++; |
| 2525 | #endif |
| 2526 | |
| 2527 | solver(cr, blocks, kblocks, xtype, outgrid, kgrid, dlev); |
| 2528 | |
| 2529 | #ifdef STANDALONE_SOLVER |
| 2530 | solver_recurse_depth--; |
| 2531 | if (solver_show_working) { |
| 2532 | printf("%*sretracting %d at (%d,%d)\n", |
| 2533 | solver_recurse_depth*4, "", list[i], x + 1, y + 1); |
| 2534 | } |
| 2535 | #endif |
| 2536 | |
| 2537 | /* |
| 2538 | * If we have our first solution, copy it into the |
| 2539 | * grid we will return. |
| 2540 | */ |
| 2541 | if (diff == DIFF_IMPOSSIBLE && dlev->diff != DIFF_IMPOSSIBLE) |
| 2542 | memcpy(grid, outgrid, cr*cr); |
| 2543 | |
| 2544 | if (dlev->diff == DIFF_AMBIGUOUS) |
| 2545 | diff = DIFF_AMBIGUOUS; |
| 2546 | else if (dlev->diff == DIFF_IMPOSSIBLE) |
| 2547 | /* do not change our return value */; |
| 2548 | else { |
| 2549 | /* the recursion turned up exactly one solution */ |
| 2550 | if (diff == DIFF_IMPOSSIBLE) |
| 2551 | diff = DIFF_RECURSIVE; |
| 2552 | else |
| 2553 | diff = DIFF_AMBIGUOUS; |
| 2554 | } |
| 2555 | |
| 2556 | /* |
| 2557 | * As soon as we've found more than one solution, |
| 2558 | * give up immediately. |
| 2559 | */ |
| 2560 | if (diff == DIFF_AMBIGUOUS) |
| 2561 | break; |
| 2562 | } |
| 2563 | |
| 2564 | sfree(outgrid); |
| 2565 | sfree(ingrid); |
| 2566 | sfree(list); |
| 2567 | } |
| 2568 | |
| 2569 | } else { |
| 2570 | /* |
| 2571 | * We're forbidden to use recursion, so we just see whether |
| 2572 | * our grid is fully solved, and return DIFF_IMPOSSIBLE |
| 2573 | * otherwise. |
| 2574 | */ |
| 2575 | for (y = 0; y < cr; y++) |
| 2576 | for (x = 0; x < cr; x++) |
| 2577 | if (!grid[y*cr+x]) |
| 2578 | diff = DIFF_IMPOSSIBLE; |
| 2579 | } |
| 2580 | |
| 2581 | got_result: |
| 2582 | dlev->diff = diff; |
| 2583 | dlev->kdiff = kdiff; |
| 2584 | |
| 2585 | #ifdef STANDALONE_SOLVER |
| 2586 | if (solver_show_working) |
| 2587 | printf("%*s%s found\n", |
| 2588 | solver_recurse_depth*4, "", |
| 2589 | diff == DIFF_IMPOSSIBLE ? "no solution" : |
| 2590 | diff == DIFF_AMBIGUOUS ? "multiple solutions" : |
| 2591 | "one solution"); |
| 2592 | #endif |
| 2593 | |
| 2594 | sfree(usage->sq2region); |
| 2595 | sfree(usage->regions); |
| 2596 | sfree(usage->cube); |
| 2597 | sfree(usage->row); |
| 2598 | sfree(usage->col); |
| 2599 | sfree(usage->blk); |
| 2600 | if (usage->kblocks) { |
| 2601 | free_block_structure(usage->kblocks); |
| 2602 | free_block_structure(usage->extra_cages); |
| 2603 | sfree(usage->extra_clues); |
| 2604 | } |
| 2605 | if (usage->kclues) sfree(usage->kclues); |
| 2606 | sfree(usage); |
| 2607 | |
| 2608 | solver_free_scratch(scratch); |
| 2609 | } |
| 2610 | |
| 2611 | /* ---------------------------------------------------------------------- |
| 2612 | * End of solver code. |
| 2613 | */ |
| 2614 | |
| 2615 | /* ---------------------------------------------------------------------- |
| 2616 | * Killer set generator. |
| 2617 | */ |
| 2618 | |
| 2619 | /* ---------------------------------------------------------------------- |
| 2620 | * Solo filled-grid generator. |
| 2621 | * |
| 2622 | * This grid generator works by essentially trying to solve a grid |
| 2623 | * starting from no clues, and not worrying that there's more than |
| 2624 | * one possible solution. Unfortunately, it isn't computationally |
| 2625 | * feasible to do this by calling the above solver with an empty |
| 2626 | * grid, because that one needs to allocate a lot of scratch space |
| 2627 | * at every recursion level. Instead, I have a much simpler |
| 2628 | * algorithm which I shamelessly copied from a Python solver |
| 2629 | * written by Andrew Wilkinson (which is GPLed, but I've reused |
| 2630 | * only ideas and no code). It mostly just does the obvious |
| 2631 | * recursive thing: pick an empty square, put one of the possible |
| 2632 | * digits in it, recurse until all squares are filled, backtrack |
| 2633 | * and change some choices if necessary. |
| 2634 | * |
| 2635 | * The clever bit is that every time it chooses which square to |
| 2636 | * fill in next, it does so by counting the number of _possible_ |
| 2637 | * numbers that can go in each square, and it prioritises so that |
| 2638 | * it picks a square with the _lowest_ number of possibilities. The |
| 2639 | * idea is that filling in lots of the obvious bits (particularly |
| 2640 | * any squares with only one possibility) will cut down on the list |
| 2641 | * of possibilities for other squares and hence reduce the enormous |
| 2642 | * search space as much as possible as early as possible. |
| 2643 | * |
| 2644 | * The use of bit sets implies that we support puzzles up to a size of |
| 2645 | * 32x32 (less if anyone finds a 16-bit machine to compile this on). |
| 2646 | */ |
| 2647 | |
| 2648 | /* |
| 2649 | * Internal data structure used in gridgen to keep track of |
| 2650 | * progress. |
| 2651 | */ |
| 2652 | struct gridgen_coord { int x, y, r; }; |
| 2653 | struct gridgen_usage { |
| 2654 | int cr; |
| 2655 | struct block_structure *blocks, *kblocks; |
| 2656 | /* grid is a copy of the input grid, modified as we go along */ |
| 2657 | digit *grid; |
| 2658 | /* |
| 2659 | * Bitsets. In each of them, bit n is set if digit n has been placed |
| 2660 | * in the corresponding region. row, col and blk are used for all |
| 2661 | * puzzles. cge is used only for killer puzzles, and diag is used |
| 2662 | * only for x-type puzzles. |
| 2663 | * All of these have cr entries, except diag which only has 2, |
| 2664 | * and cge, which has as many entries as kblocks. |
| 2665 | */ |
| 2666 | unsigned int *row, *col, *blk, *cge, *diag; |
| 2667 | /* This lists all the empty spaces remaining in the grid. */ |
| 2668 | struct gridgen_coord *spaces; |
| 2669 | int nspaces; |
| 2670 | /* If we need randomisation in the solve, this is our random state. */ |
| 2671 | random_state *rs; |
| 2672 | }; |
| 2673 | |
| 2674 | static void gridgen_place(struct gridgen_usage *usage, int x, int y, digit n) |
| 2675 | { |
| 2676 | unsigned int bit = 1 << n; |
| 2677 | int cr = usage->cr; |
| 2678 | usage->row[y] |= bit; |
| 2679 | usage->col[x] |= bit; |
| 2680 | usage->blk[usage->blocks->whichblock[y*cr+x]] |= bit; |
| 2681 | if (usage->cge) |
| 2682 | usage->cge[usage->kblocks->whichblock[y*cr+x]] |= bit; |
| 2683 | if (usage->diag) { |
| 2684 | if (ondiag0(y*cr+x)) |
| 2685 | usage->diag[0] |= bit; |
| 2686 | if (ondiag1(y*cr+x)) |
| 2687 | usage->diag[1] |= bit; |
| 2688 | } |
| 2689 | usage->grid[y*cr+x] = n; |
| 2690 | } |
| 2691 | |
| 2692 | static void gridgen_remove(struct gridgen_usage *usage, int x, int y, digit n) |
| 2693 | { |
| 2694 | unsigned int mask = ~(1 << n); |
| 2695 | int cr = usage->cr; |
| 2696 | usage->row[y] &= mask; |
| 2697 | usage->col[x] &= mask; |
| 2698 | usage->blk[usage->blocks->whichblock[y*cr+x]] &= mask; |
| 2699 | if (usage->cge) |
| 2700 | usage->cge[usage->kblocks->whichblock[y*cr+x]] &= mask; |
| 2701 | if (usage->diag) { |
| 2702 | if (ondiag0(y*cr+x)) |
| 2703 | usage->diag[0] &= mask; |
| 2704 | if (ondiag1(y*cr+x)) |
| 2705 | usage->diag[1] &= mask; |
| 2706 | } |
| 2707 | usage->grid[y*cr+x] = 0; |
| 2708 | } |
| 2709 | |
| 2710 | #define N_SINGLE 32 |
| 2711 | |
| 2712 | /* |
| 2713 | * The real recursive step in the generating function. |
| 2714 | * |
| 2715 | * Return values: 1 means solution found, 0 means no solution |
| 2716 | * found on this branch. |
| 2717 | */ |
| 2718 | static int gridgen_real(struct gridgen_usage *usage, digit *grid, int *steps) |
| 2719 | { |
| 2720 | int cr = usage->cr; |
| 2721 | int i, j, n, sx, sy, bestm, bestr, ret; |
| 2722 | int *digits; |
| 2723 | unsigned int used; |
| 2724 | |
| 2725 | /* |
| 2726 | * Firstly, check for completion! If there are no spaces left |
| 2727 | * in the grid, we have a solution. |
| 2728 | */ |
| 2729 | if (usage->nspaces == 0) |
| 2730 | return TRUE; |
| 2731 | |
| 2732 | /* |
| 2733 | * Next, abandon generation if we went over our steps limit. |
| 2734 | */ |
| 2735 | if (*steps <= 0) |
| 2736 | return FALSE; |
| 2737 | (*steps)--; |
| 2738 | |
| 2739 | /* |
| 2740 | * Otherwise, there must be at least one space. Find the most |
| 2741 | * constrained space, using the `r' field as a tie-breaker. |
| 2742 | */ |
| 2743 | bestm = cr+1; /* so that any space will beat it */ |
| 2744 | bestr = 0; |
| 2745 | used = ~0; |
| 2746 | i = sx = sy = -1; |
| 2747 | for (j = 0; j < usage->nspaces; j++) { |
| 2748 | int x = usage->spaces[j].x, y = usage->spaces[j].y; |
| 2749 | unsigned int used_xy; |
| 2750 | int m; |
| 2751 | |
| 2752 | m = usage->blocks->whichblock[y*cr+x]; |
| 2753 | used_xy = usage->row[y] | usage->col[x] | usage->blk[m]; |
| 2754 | if (usage->cge != NULL) |
| 2755 | used_xy |= usage->cge[usage->kblocks->whichblock[y*cr+x]]; |
| 2756 | if (usage->cge != NULL) |
| 2757 | used_xy |= usage->cge[usage->kblocks->whichblock[y*cr+x]]; |
| 2758 | if (usage->diag != NULL) { |
| 2759 | if (ondiag0(y*cr+x)) |
| 2760 | used_xy |= usage->diag[0]; |
| 2761 | if (ondiag1(y*cr+x)) |
| 2762 | used_xy |= usage->diag[1]; |
| 2763 | } |
| 2764 | |
| 2765 | /* |
| 2766 | * Find the number of digits that could go in this space. |
| 2767 | */ |
| 2768 | m = 0; |
| 2769 | for (n = 1; n <= cr; n++) { |
| 2770 | unsigned int bit = 1 << n; |
| 2771 | if ((used_xy & bit) == 0) |
| 2772 | m++; |
| 2773 | } |
| 2774 | if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) { |
| 2775 | bestm = m; |
| 2776 | bestr = usage->spaces[j].r; |
| 2777 | sx = x; |
| 2778 | sy = y; |
| 2779 | i = j; |
| 2780 | used = used_xy; |
| 2781 | } |
| 2782 | } |
| 2783 | |
| 2784 | /* |
| 2785 | * Swap that square into the final place in the spaces array, |
| 2786 | * so that decrementing nspaces will remove it from the list. |
| 2787 | */ |
| 2788 | if (i != usage->nspaces-1) { |
| 2789 | struct gridgen_coord t; |
| 2790 | t = usage->spaces[usage->nspaces-1]; |
| 2791 | usage->spaces[usage->nspaces-1] = usage->spaces[i]; |
| 2792 | usage->spaces[i] = t; |
| 2793 | } |
| 2794 | |
| 2795 | /* |
| 2796 | * Now we've decided which square to start our recursion at, |
| 2797 | * simply go through all possible values, shuffling them |
| 2798 | * randomly first if necessary. |
| 2799 | */ |
| 2800 | digits = snewn(bestm, int); |
| 2801 | |
| 2802 | j = 0; |
| 2803 | for (n = 1; n <= cr; n++) { |
| 2804 | unsigned int bit = 1 << n; |
| 2805 | |
| 2806 | if ((used & bit) == 0) |
| 2807 | digits[j++] = n; |
| 2808 | } |
| 2809 | |
| 2810 | if (usage->rs) |
| 2811 | shuffle(digits, j, sizeof(*digits), usage->rs); |
| 2812 | |
| 2813 | /* And finally, go through the digit list and actually recurse. */ |
| 2814 | ret = FALSE; |
| 2815 | for (i = 0; i < j; i++) { |
| 2816 | n = digits[i]; |
| 2817 | |
| 2818 | /* Update the usage structure to reflect the placing of this digit. */ |
| 2819 | gridgen_place(usage, sx, sy, n); |
| 2820 | usage->nspaces--; |
| 2821 | |
| 2822 | /* Call the solver recursively. Stop when we find a solution. */ |
| 2823 | if (gridgen_real(usage, grid, steps)) { |
| 2824 | ret = TRUE; |
| 2825 | break; |
| 2826 | } |
| 2827 | |
| 2828 | /* Revert the usage structure. */ |
| 2829 | gridgen_remove(usage, sx, sy, n); |
| 2830 | usage->nspaces++; |
| 2831 | } |
| 2832 | |
| 2833 | sfree(digits); |
| 2834 | return ret; |
| 2835 | } |
| 2836 | |
| 2837 | /* |
| 2838 | * Entry point to generator. You give it parameters and a starting |
| 2839 | * grid, which is simply an array of cr*cr digits. |
| 2840 | */ |
| 2841 | static int gridgen(int cr, struct block_structure *blocks, |
| 2842 | struct block_structure *kblocks, int xtype, |
| 2843 | digit *grid, random_state *rs, int maxsteps) |
| 2844 | { |
| 2845 | struct gridgen_usage *usage; |
| 2846 | int x, y, ret; |
| 2847 | |
| 2848 | /* |
| 2849 | * Clear the grid to start with. |
| 2850 | */ |
| 2851 | memset(grid, 0, cr*cr); |
| 2852 | |
| 2853 | /* |
| 2854 | * Create a gridgen_usage structure. |
| 2855 | */ |
| 2856 | usage = snew(struct gridgen_usage); |
| 2857 | |
| 2858 | usage->cr = cr; |
| 2859 | usage->blocks = blocks; |
| 2860 | |
| 2861 | usage->grid = grid; |
| 2862 | |
| 2863 | usage->row = snewn(cr, unsigned int); |
| 2864 | usage->col = snewn(cr, unsigned int); |
| 2865 | usage->blk = snewn(cr, unsigned int); |
| 2866 | if (kblocks != NULL) { |
| 2867 | usage->kblocks = kblocks; |
| 2868 | usage->cge = snewn(usage->kblocks->nr_blocks, unsigned int); |
| 2869 | memset(usage->cge, FALSE, kblocks->nr_blocks * sizeof *usage->cge); |
| 2870 | } else { |
| 2871 | usage->cge = NULL; |
| 2872 | } |
| 2873 | |
| 2874 | memset(usage->row, 0, cr * sizeof *usage->row); |
| 2875 | memset(usage->col, 0, cr * sizeof *usage->col); |
| 2876 | memset(usage->blk, 0, cr * sizeof *usage->blk); |
| 2877 | |
| 2878 | if (xtype) { |
| 2879 | usage->diag = snewn(2, unsigned int); |
| 2880 | memset(usage->diag, 0, 2 * sizeof *usage->diag); |
| 2881 | } else { |
| 2882 | usage->diag = NULL; |
| 2883 | } |
| 2884 | |
| 2885 | /* |
| 2886 | * Begin by filling in the whole top row with randomly chosen |
| 2887 | * numbers. This cannot introduce any bias or restriction on |
| 2888 | * the available grids, since we already know those numbers |
| 2889 | * are all distinct so all we're doing is choosing their |
| 2890 | * labels. |
| 2891 | */ |
| 2892 | for (x = 0; x < cr; x++) |
| 2893 | grid[x] = x+1; |
| 2894 | shuffle(grid, cr, sizeof(*grid), rs); |
| 2895 | for (x = 0; x < cr; x++) |
| 2896 | gridgen_place(usage, x, 0, grid[x]); |
| 2897 | |
| 2898 | usage->spaces = snewn(cr * cr, struct gridgen_coord); |
| 2899 | usage->nspaces = 0; |
| 2900 | |
| 2901 | usage->rs = rs; |
| 2902 | |
| 2903 | /* |
| 2904 | * Initialise the list of grid spaces, taking care to leave |
| 2905 | * out the row I've already filled in above. |
| 2906 | */ |
| 2907 | for (y = 1; y < cr; y++) { |
| 2908 | for (x = 0; x < cr; x++) { |
| 2909 | usage->spaces[usage->nspaces].x = x; |
| 2910 | usage->spaces[usage->nspaces].y = y; |
| 2911 | usage->spaces[usage->nspaces].r = random_bits(rs, 31); |
| 2912 | usage->nspaces++; |
| 2913 | } |
| 2914 | } |
| 2915 | |
| 2916 | /* |
| 2917 | * Run the real generator function. |
| 2918 | */ |
| 2919 | ret = gridgen_real(usage, grid, &maxsteps); |
| 2920 | |
| 2921 | /* |
| 2922 | * Clean up the usage structure now we have our answer. |
| 2923 | */ |
| 2924 | sfree(usage->spaces); |
| 2925 | sfree(usage->cge); |
| 2926 | sfree(usage->blk); |
| 2927 | sfree(usage->col); |
| 2928 | sfree(usage->row); |
| 2929 | sfree(usage); |
| 2930 | |
| 2931 | return ret; |
| 2932 | } |
| 2933 | |
| 2934 | /* ---------------------------------------------------------------------- |
| 2935 | * End of grid generator code. |
| 2936 | */ |
| 2937 | |
| 2938 | /* |
| 2939 | * Check whether a grid contains a valid complete puzzle. |
| 2940 | */ |
| 2941 | static int check_valid(int cr, struct block_structure *blocks, |
| 2942 | struct block_structure *kblocks, int xtype, digit *grid) |
| 2943 | { |
| 2944 | unsigned char *used; |
| 2945 | int x, y, i, j, n; |
| 2946 | |
| 2947 | used = snewn(cr, unsigned char); |
| 2948 | |
| 2949 | /* |
| 2950 | * Check that each row contains precisely one of everything. |
| 2951 | */ |
| 2952 | for (y = 0; y < cr; y++) { |
| 2953 | memset(used, FALSE, cr); |
| 2954 | for (x = 0; x < cr; x++) |
| 2955 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
| 2956 | used[grid[y*cr+x]-1] = TRUE; |
| 2957 | for (n = 0; n < cr; n++) |
| 2958 | if (!used[n]) { |
| 2959 | sfree(used); |
| 2960 | return FALSE; |
| 2961 | } |
| 2962 | } |
| 2963 | |
| 2964 | /* |
| 2965 | * Check that each column contains precisely one of everything. |
| 2966 | */ |
| 2967 | for (x = 0; x < cr; x++) { |
| 2968 | memset(used, FALSE, cr); |
| 2969 | for (y = 0; y < cr; y++) |
| 2970 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
| 2971 | used[grid[y*cr+x]-1] = TRUE; |
| 2972 | for (n = 0; n < cr; n++) |
| 2973 | if (!used[n]) { |
| 2974 | sfree(used); |
| 2975 | return FALSE; |
| 2976 | } |
| 2977 | } |
| 2978 | |
| 2979 | /* |
| 2980 | * Check that each block contains precisely one of everything. |
| 2981 | */ |
| 2982 | for (i = 0; i < cr; i++) { |
| 2983 | memset(used, FALSE, cr); |
| 2984 | for (j = 0; j < cr; j++) |
| 2985 | if (grid[blocks->blocks[i][j]] > 0 && |
| 2986 | grid[blocks->blocks[i][j]] <= cr) |
| 2987 | used[grid[blocks->blocks[i][j]]-1] = TRUE; |
| 2988 | for (n = 0; n < cr; n++) |
| 2989 | if (!used[n]) { |
| 2990 | sfree(used); |
| 2991 | return FALSE; |
| 2992 | } |
| 2993 | } |
| 2994 | |
| 2995 | /* |
| 2996 | * Check that each Killer cage, if any, contains at most one of |
| 2997 | * everything. |
| 2998 | */ |
| 2999 | if (kblocks) { |
| 3000 | for (i = 0; i < kblocks->nr_blocks; i++) { |
| 3001 | memset(used, FALSE, cr); |
| 3002 | for (j = 0; j < kblocks->nr_squares[i]; j++) |
| 3003 | if (grid[kblocks->blocks[i][j]] > 0 && |
| 3004 | grid[kblocks->blocks[i][j]] <= cr) { |
| 3005 | if (used[grid[kblocks->blocks[i][j]]-1]) { |
| 3006 | sfree(used); |
| 3007 | return FALSE; |
| 3008 | } |
| 3009 | used[grid[kblocks->blocks[i][j]]-1] = TRUE; |
| 3010 | } |
| 3011 | } |
| 3012 | } |
| 3013 | |
| 3014 | /* |
| 3015 | * Check that each diagonal contains precisely one of everything. |
| 3016 | */ |
| 3017 | if (xtype) { |
| 3018 | memset(used, FALSE, cr); |
| 3019 | for (i = 0; i < cr; i++) |
| 3020 | if (grid[diag0(i)] > 0 && grid[diag0(i)] <= cr) |
| 3021 | used[grid[diag0(i)]-1] = TRUE; |
| 3022 | for (n = 0; n < cr; n++) |
| 3023 | if (!used[n]) { |
| 3024 | sfree(used); |
| 3025 | return FALSE; |
| 3026 | } |
| 3027 | for (i = 0; i < cr; i++) |
| 3028 | if (grid[diag1(i)] > 0 && grid[diag1(i)] <= cr) |
| 3029 | used[grid[diag1(i)]-1] = TRUE; |
| 3030 | for (n = 0; n < cr; n++) |
| 3031 | if (!used[n]) { |
| 3032 | sfree(used); |
| 3033 | return FALSE; |
| 3034 | } |
| 3035 | } |
| 3036 | |
| 3037 | sfree(used); |
| 3038 | return TRUE; |
| 3039 | } |
| 3040 | |
| 3041 | static int symmetries(game_params *params, int x, int y, int *output, int s) |
| 3042 | { |
| 3043 | int c = params->c, r = params->r, cr = c*r; |
| 3044 | int i = 0; |
| 3045 | |
| 3046 | #define ADD(x,y) (*output++ = (x), *output++ = (y), i++) |
| 3047 | |
| 3048 | ADD(x, y); |
| 3049 | |
| 3050 | switch (s) { |
| 3051 | case SYMM_NONE: |
| 3052 | break; /* just x,y is all we need */ |
| 3053 | case SYMM_ROT2: |
| 3054 | ADD(cr - 1 - x, cr - 1 - y); |
| 3055 | break; |
| 3056 | case SYMM_ROT4: |
| 3057 | ADD(cr - 1 - y, x); |
| 3058 | ADD(y, cr - 1 - x); |
| 3059 | ADD(cr - 1 - x, cr - 1 - y); |
| 3060 | break; |
| 3061 | case SYMM_REF2: |
| 3062 | ADD(cr - 1 - x, y); |
| 3063 | break; |
| 3064 | case SYMM_REF2D: |
| 3065 | ADD(y, x); |
| 3066 | break; |
| 3067 | case SYMM_REF4: |
| 3068 | ADD(cr - 1 - x, y); |
| 3069 | ADD(x, cr - 1 - y); |
| 3070 | ADD(cr - 1 - x, cr - 1 - y); |
| 3071 | break; |
| 3072 | case SYMM_REF4D: |
| 3073 | ADD(y, x); |
| 3074 | ADD(cr - 1 - x, cr - 1 - y); |
| 3075 | ADD(cr - 1 - y, cr - 1 - x); |
| 3076 | break; |
| 3077 | case SYMM_REF8: |
| 3078 | ADD(cr - 1 - x, y); |
| 3079 | ADD(x, cr - 1 - y); |
| 3080 | ADD(cr - 1 - x, cr - 1 - y); |
| 3081 | ADD(y, x); |
| 3082 | ADD(y, cr - 1 - x); |
| 3083 | ADD(cr - 1 - y, x); |
| 3084 | ADD(cr - 1 - y, cr - 1 - x); |
| 3085 | break; |
| 3086 | } |
| 3087 | |
| 3088 | #undef ADD |
| 3089 | |
| 3090 | return i; |
| 3091 | } |
| 3092 | |
| 3093 | static char *encode_solve_move(int cr, digit *grid) |
| 3094 | { |
| 3095 | int i, len; |
| 3096 | char *ret, *p, *sep; |
| 3097 | |
| 3098 | /* |
| 3099 | * It's surprisingly easy to work out _exactly_ how long this |
| 3100 | * string needs to be. To decimal-encode all the numbers from 1 |
| 3101 | * to n: |
| 3102 | * |
| 3103 | * - every number has a units digit; total is n. |
| 3104 | * - all numbers above 9 have a tens digit; total is max(n-9,0). |
| 3105 | * - all numbers above 99 have a hundreds digit; total is max(n-99,0). |
| 3106 | * - and so on. |
| 3107 | */ |
| 3108 | len = 0; |
| 3109 | for (i = 1; i <= cr; i *= 10) |
| 3110 | len += max(cr - i + 1, 0); |
| 3111 | len += cr; /* don't forget the commas */ |
| 3112 | len *= cr; /* there are cr rows of these */ |
| 3113 | |
| 3114 | /* |
| 3115 | * Now len is one bigger than the total size of the |
| 3116 | * comma-separated numbers (because we counted an |
| 3117 | * additional leading comma). We need to have a leading S |
| 3118 | * and a trailing NUL, so we're off by one in total. |
| 3119 | */ |
| 3120 | len++; |
| 3121 | |
| 3122 | ret = snewn(len, char); |
| 3123 | p = ret; |
| 3124 | *p++ = 'S'; |
| 3125 | sep = ""; |
| 3126 | for (i = 0; i < cr*cr; i++) { |
| 3127 | p += sprintf(p, "%s%d", sep, grid[i]); |
| 3128 | sep = ","; |
| 3129 | } |
| 3130 | *p++ = '\0'; |
| 3131 | assert(p - ret == len); |
| 3132 | |
| 3133 | return ret; |
| 3134 | } |
| 3135 | |
| 3136 | static void dsf_to_blocks(int *dsf, struct block_structure *blocks, |
| 3137 | int min_expected, int max_expected) |
| 3138 | { |
| 3139 | int cr = blocks->c * blocks->r, area = cr * cr; |
| 3140 | int i, nb = 0; |
| 3141 | |
| 3142 | for (i = 0; i < area; i++) |
| 3143 | blocks->whichblock[i] = -1; |
| 3144 | for (i = 0; i < area; i++) { |
| 3145 | int j = dsf_canonify(dsf, i); |
| 3146 | if (blocks->whichblock[j] < 0) |
| 3147 | blocks->whichblock[j] = nb++; |
| 3148 | blocks->whichblock[i] = blocks->whichblock[j]; |
| 3149 | } |
| 3150 | assert(nb >= min_expected && nb <= max_expected); |
| 3151 | blocks->nr_blocks = nb; |
| 3152 | } |
| 3153 | |
| 3154 | static void make_blocks_from_whichblock(struct block_structure *blocks) |
| 3155 | { |
| 3156 | int i; |
| 3157 | |
| 3158 | for (i = 0; i < blocks->nr_blocks; i++) { |
| 3159 | blocks->blocks[i][blocks->max_nr_squares-1] = 0; |
| 3160 | blocks->nr_squares[i] = 0; |
| 3161 | } |
| 3162 | for (i = 0; i < blocks->area; i++) { |
| 3163 | int b = blocks->whichblock[i]; |
| 3164 | int j = blocks->blocks[b][blocks->max_nr_squares-1]++; |
| 3165 | assert(j < blocks->max_nr_squares); |
| 3166 | blocks->blocks[b][j] = i; |
| 3167 | blocks->nr_squares[b]++; |
| 3168 | } |
| 3169 | } |
| 3170 | |
| 3171 | static char *encode_block_structure_desc(char *p, struct block_structure *blocks) |
| 3172 | { |
| 3173 | int i, currrun = 0; |
| 3174 | int c = blocks->c, r = blocks->r, cr = c * r; |
| 3175 | |
| 3176 | /* |
| 3177 | * Encode the block structure. We do this by encoding |
| 3178 | * the pattern of dividing lines: first we iterate |
| 3179 | * over the cr*(cr-1) internal vertical grid lines in |
| 3180 | * ordinary reading order, then over the cr*(cr-1) |
| 3181 | * internal horizontal ones in transposed reading |
| 3182 | * order. |
| 3183 | * |
| 3184 | * We encode the number of non-lines between the |
| 3185 | * lines; _ means zero (two adjacent divisions), a |
| 3186 | * means 1, ..., y means 25, and z means 25 non-lines |
| 3187 | * _and no following line_ (so that za means 26, zb 27 |
| 3188 | * etc). |
| 3189 | */ |
| 3190 | for (i = 0; i <= 2*cr*(cr-1); i++) { |
| 3191 | int x, y, p0, p1, edge; |
| 3192 | |
| 3193 | if (i == 2*cr*(cr-1)) { |
| 3194 | edge = TRUE; /* terminating virtual edge */ |
| 3195 | } else { |
| 3196 | if (i < cr*(cr-1)) { |
| 3197 | y = i/(cr-1); |
| 3198 | x = i%(cr-1); |
| 3199 | p0 = y*cr+x; |
| 3200 | p1 = y*cr+x+1; |
| 3201 | } else { |
| 3202 | x = i/(cr-1) - cr; |
| 3203 | y = i%(cr-1); |
| 3204 | p0 = y*cr+x; |
| 3205 | p1 = (y+1)*cr+x; |
| 3206 | } |
| 3207 | edge = (blocks->whichblock[p0] != blocks->whichblock[p1]); |
| 3208 | } |
| 3209 | |
| 3210 | if (edge) { |
| 3211 | while (currrun > 25) |
| 3212 | *p++ = 'z', currrun -= 25; |
| 3213 | if (currrun) |
| 3214 | *p++ = 'a'-1 + currrun; |
| 3215 | else |
| 3216 | *p++ = '_'; |
| 3217 | currrun = 0; |
| 3218 | } else |
| 3219 | currrun++; |
| 3220 | } |
| 3221 | return p; |
| 3222 | } |
| 3223 | |
| 3224 | static char *encode_grid(char *desc, digit *grid, int area) |
| 3225 | { |
| 3226 | int run, i; |
| 3227 | char *p = desc; |
| 3228 | |
| 3229 | run = 0; |
| 3230 | for (i = 0; i <= area; i++) { |
| 3231 | int n = (i < area ? grid[i] : -1); |
| 3232 | |
| 3233 | if (!n) |
| 3234 | run++; |
| 3235 | else { |
| 3236 | if (run) { |
| 3237 | while (run > 0) { |
| 3238 | int c = 'a' - 1 + run; |
| 3239 | if (run > 26) |
| 3240 | c = 'z'; |
| 3241 | *p++ = c; |
| 3242 | run -= c - ('a' - 1); |
| 3243 | } |
| 3244 | } else { |
| 3245 | /* |
| 3246 | * If there's a number in the very top left or |
| 3247 | * bottom right, there's no point putting an |
| 3248 | * unnecessary _ before or after it. |
| 3249 | */ |
| 3250 | if (p > desc && n > 0) |
| 3251 | *p++ = '_'; |
| 3252 | } |
| 3253 | if (n > 0) |
| 3254 | p += sprintf(p, "%d", n); |
| 3255 | run = 0; |
| 3256 | } |
| 3257 | } |
| 3258 | return p; |
| 3259 | } |
| 3260 | |
| 3261 | /* |
| 3262 | * Conservatively stimate the number of characters required for |
| 3263 | * encoding a grid of a certain area. |
| 3264 | */ |
| 3265 | static int grid_encode_space (int area) |
| 3266 | { |
| 3267 | int t, count; |
| 3268 | for (count = 1, t = area; t > 26; t -= 26) |
| 3269 | count++; |
| 3270 | return count * area; |
| 3271 | } |
| 3272 | |
| 3273 | /* |
| 3274 | * Conservatively stimate the number of characters required for |
| 3275 | * encoding a given blocks structure. |
| 3276 | */ |
| 3277 | static int blocks_encode_space(struct block_structure *blocks) |
| 3278 | { |
| 3279 | int cr = blocks->c * blocks->r, area = cr * cr; |
| 3280 | return grid_encode_space(area); |
| 3281 | } |
| 3282 | |
| 3283 | static char *encode_puzzle_desc(game_params *params, digit *grid, |
| 3284 | struct block_structure *blocks, |
| 3285 | digit *kgrid, |
| 3286 | struct block_structure *kblocks) |
| 3287 | { |
| 3288 | int c = params->c, r = params->r, cr = c*r; |
| 3289 | int area = cr*cr; |
| 3290 | char *p, *desc; |
| 3291 | int space; |
| 3292 | |
| 3293 | space = grid_encode_space(area) + 1; |
| 3294 | if (r == 1) |
| 3295 | space += blocks_encode_space(blocks) + 1; |
| 3296 | if (params->killer) { |
| 3297 | space += blocks_encode_space(kblocks) + 1; |
| 3298 | space += grid_encode_space(area) + 1; |
| 3299 | } |
| 3300 | desc = snewn(space, char); |
| 3301 | p = encode_grid(desc, grid, area); |
| 3302 | |
| 3303 | if (r == 1) { |
| 3304 | *p++ = ','; |
| 3305 | p = encode_block_structure_desc(p, blocks); |
| 3306 | } |
| 3307 | if (params->killer) { |
| 3308 | *p++ = ','; |
| 3309 | p = encode_block_structure_desc(p, kblocks); |
| 3310 | *p++ = ','; |
| 3311 | p = encode_grid(p, kgrid, area); |
| 3312 | } |
| 3313 | assert(p - desc < space); |
| 3314 | *p++ = '\0'; |
| 3315 | desc = sresize(desc, p - desc, char); |
| 3316 | |
| 3317 | return desc; |
| 3318 | } |
| 3319 | |
| 3320 | static void merge_blocks(struct block_structure *b, int n1, int n2) |
| 3321 | { |
| 3322 | int i; |
| 3323 | /* Move data towards the lower block number. */ |
| 3324 | if (n2 < n1) { |
| 3325 | int t = n2; |
| 3326 | n2 = n1; |
| 3327 | n1 = t; |
| 3328 | } |
| 3329 | |
| 3330 | /* Merge n2 into n1, and move the last block into n2's position. */ |
| 3331 | for (i = 0; i < b->nr_squares[n2]; i++) |
| 3332 | b->whichblock[b->blocks[n2][i]] = n1; |
| 3333 | memcpy(b->blocks[n1] + b->nr_squares[n1], b->blocks[n2], |
| 3334 | b->nr_squares[n2] * sizeof **b->blocks); |
| 3335 | b->nr_squares[n1] += b->nr_squares[n2]; |
| 3336 | |
| 3337 | n1 = b->nr_blocks - 1; |
| 3338 | if (n2 != n1) { |
| 3339 | memcpy(b->blocks[n2], b->blocks[n1], |
| 3340 | b->nr_squares[n1] * sizeof **b->blocks); |
| 3341 | for (i = 0; i < b->nr_squares[n1]; i++) |
| 3342 | b->whichblock[b->blocks[n1][i]] = n2; |
| 3343 | b->nr_squares[n2] = b->nr_squares[n1]; |
| 3344 | } |
| 3345 | b->nr_blocks = n1; |
| 3346 | } |
| 3347 | |
| 3348 | static int merge_some_cages(struct block_structure *b, int cr, int area, |
| 3349 | digit *grid, random_state *rs) |
| 3350 | { |
| 3351 | /* |
| 3352 | * Make a list of all the pairs of adjacent blocks. |
| 3353 | */ |
| 3354 | int i, j, k; |
| 3355 | struct pair { |
| 3356 | int b1, b2; |
| 3357 | } *pairs; |
| 3358 | int npairs; |
| 3359 | |
| 3360 | pairs = snewn(b->nr_blocks * b->nr_blocks, struct pair); |
| 3361 | npairs = 0; |
| 3362 | |
| 3363 | for (i = 0; i < b->nr_blocks; i++) { |
| 3364 | for (j = i+1; j < b->nr_blocks; j++) { |
| 3365 | |
| 3366 | /* |
| 3367 | * Rule the merger out of consideration if it's |
| 3368 | * obviously not viable. |
| 3369 | */ |
| 3370 | if (b->nr_squares[i] + b->nr_squares[j] > b->max_nr_squares) |
| 3371 | continue; /* we couldn't merge these anyway */ |
| 3372 | |
| 3373 | /* |
| 3374 | * See if these two blocks have a pair of squares |
| 3375 | * adjacent to each other. |
| 3376 | */ |
| 3377 | for (k = 0; k < b->nr_squares[i]; k++) { |
| 3378 | int xy = b->blocks[i][k]; |
| 3379 | int y = xy / cr, x = xy % cr; |
| 3380 | if ((y > 0 && b->whichblock[xy - cr] == j) || |
| 3381 | (y+1 < cr && b->whichblock[xy + cr] == j) || |
| 3382 | (x > 0 && b->whichblock[xy - 1] == j) || |
| 3383 | (x+1 < cr && b->whichblock[xy + 1] == j)) { |
| 3384 | /* |
| 3385 | * Yes! Add this pair to our list. |
| 3386 | */ |
| 3387 | pairs[npairs].b1 = i; |
| 3388 | pairs[npairs].b2 = j; |
| 3389 | break; |
| 3390 | } |
| 3391 | } |
| 3392 | } |
| 3393 | } |
| 3394 | |
| 3395 | /* |
| 3396 | * Now go through that list in random order until we find a pair |
| 3397 | * of blocks we can merge. |
| 3398 | */ |
| 3399 | while (npairs > 0) { |
| 3400 | int n1, n2; |
| 3401 | unsigned int digits_found; |
| 3402 | |
| 3403 | /* |
| 3404 | * Pick a random pair, and remove it from the list. |
| 3405 | */ |
| 3406 | i = random_upto(rs, npairs); |
| 3407 | n1 = pairs[i].b1; |
| 3408 | n2 = pairs[i].b2; |
| 3409 | if (i != npairs-1) |
| 3410 | pairs[i] = pairs[npairs-1]; |
| 3411 | npairs--; |
| 3412 | |
| 3413 | /* Guarantee that the merged cage would still be a region. */ |
| 3414 | digits_found = 0; |
| 3415 | for (i = 0; i < b->nr_squares[n1]; i++) |
| 3416 | digits_found |= 1 << grid[b->blocks[n1][i]]; |
| 3417 | for (i = 0; i < b->nr_squares[n2]; i++) |
| 3418 | if (digits_found & (1 << grid[b->blocks[n2][i]])) |
| 3419 | break; |
| 3420 | if (i != b->nr_squares[n2]) |
| 3421 | continue; |
| 3422 | |
| 3423 | /* |
| 3424 | * Got one! Do the merge. |
| 3425 | */ |
| 3426 | merge_blocks(b, n1, n2); |
| 3427 | sfree(pairs); |
| 3428 | return TRUE; |
| 3429 | } |
| 3430 | |
| 3431 | sfree(pairs); |
| 3432 | return FALSE; |
| 3433 | } |
| 3434 | |
| 3435 | static void compute_kclues(struct block_structure *cages, digit *kclues, |
| 3436 | digit *grid, int area) |
| 3437 | { |
| 3438 | int i; |
| 3439 | memset(kclues, 0, area * sizeof *kclues); |
| 3440 | for (i = 0; i < cages->nr_blocks; i++) { |
| 3441 | int j, sum = 0; |
| 3442 | for (j = 0; j < area; j++) |
| 3443 | if (cages->whichblock[j] == i) |
| 3444 | sum += grid[j]; |
| 3445 | for (j = 0; j < area; j++) |
| 3446 | if (cages->whichblock[j] == i) |
| 3447 | break; |
| 3448 | assert (j != area); |
| 3449 | kclues[j] = sum; |
| 3450 | } |
| 3451 | } |
| 3452 | |
| 3453 | static struct block_structure *gen_killer_cages(int cr, random_state *rs, |
| 3454 | int remove_singletons) |
| 3455 | { |
| 3456 | int nr; |
| 3457 | int x, y, area = cr * cr; |
| 3458 | int n_singletons = 0; |
| 3459 | struct block_structure *b = alloc_block_structure (1, cr, area, cr, area); |
| 3460 | |
| 3461 | for (x = 0; x < area; x++) |
| 3462 | b->whichblock[x] = -1; |
| 3463 | nr = 0; |
| 3464 | for (y = 0; y < cr; y++) |
| 3465 | for (x = 0; x < cr; x++) { |
| 3466 | int rnd; |
| 3467 | int xy = y*cr+x; |
| 3468 | if (b->whichblock[xy] != -1) |
| 3469 | continue; |
| 3470 | b->whichblock[xy] = nr; |
| 3471 | |
| 3472 | rnd = random_bits(rs, 4); |
| 3473 | if (xy + 1 < area && (rnd >= 4 || (!remove_singletons && rnd >= 1))) { |
| 3474 | int xy2 = xy + 1; |
| 3475 | if (x + 1 == cr || b->whichblock[xy2] != -1 || |
| 3476 | (xy + cr < area && random_bits(rs, 1) == 0)) |
| 3477 | xy2 = xy + cr; |
| 3478 | if (xy2 >= area) |
| 3479 | n_singletons++; |
| 3480 | else |
| 3481 | b->whichblock[xy2] = nr; |
| 3482 | } else |
| 3483 | n_singletons++; |
| 3484 | nr++; |
| 3485 | } |
| 3486 | |
| 3487 | b->nr_blocks = nr; |
| 3488 | make_blocks_from_whichblock(b); |
| 3489 | |
| 3490 | for (x = y = 0; x < b->nr_blocks; x++) |
| 3491 | if (b->nr_squares[x] == 1) |
| 3492 | y++; |
| 3493 | assert(y == n_singletons); |
| 3494 | |
| 3495 | if (n_singletons > 0 && remove_singletons) { |
| 3496 | int n; |
| 3497 | for (n = 0; n < b->nr_blocks;) { |
| 3498 | int xy, x, y, xy2, other; |
| 3499 | if (b->nr_squares[n] > 1) { |
| 3500 | n++; |
| 3501 | continue; |
| 3502 | } |
| 3503 | xy = b->blocks[n][0]; |
| 3504 | x = xy % cr; |
| 3505 | y = xy / cr; |
| 3506 | if (xy + 1 == area) |
| 3507 | xy2 = xy - 1; |
| 3508 | else if (x + 1 < cr && (y + 1 == cr || random_bits(rs, 1) == 0)) |
| 3509 | xy2 = xy + 1; |
| 3510 | else |
| 3511 | xy2 = xy + cr; |
| 3512 | other = b->whichblock[xy2]; |
| 3513 | |
| 3514 | if (b->nr_squares[other] == 1) |
| 3515 | n_singletons--; |
| 3516 | n_singletons--; |
| 3517 | merge_blocks(b, n, other); |
| 3518 | if (n < other) |
| 3519 | n++; |
| 3520 | } |
| 3521 | assert(n_singletons == 0); |
| 3522 | } |
| 3523 | return b; |
| 3524 | } |
| 3525 | |
| 3526 | static char *new_game_desc(game_params *params, random_state *rs, |
| 3527 | char **aux, int interactive) |
| 3528 | { |
| 3529 | int c = params->c, r = params->r, cr = c*r; |
| 3530 | int area = cr*cr; |
| 3531 | struct block_structure *blocks, *kblocks; |
| 3532 | digit *grid, *grid2, *kgrid; |
| 3533 | struct xy { int x, y; } *locs; |
| 3534 | int nlocs; |
| 3535 | char *desc; |
| 3536 | int coords[16], ncoords; |
| 3537 | int x, y, i, j; |
| 3538 | struct difficulty dlev; |
| 3539 | |
| 3540 | precompute_sum_bits(); |
| 3541 | |
| 3542 | /* |
| 3543 | * Adjust the maximum difficulty level to be consistent with |
| 3544 | * the puzzle size: all 2x2 puzzles appear to be Trivial |
| 3545 | * (DIFF_BLOCK) so we cannot hold out for even a Basic |
| 3546 | * (DIFF_SIMPLE) one. |
| 3547 | */ |
| 3548 | dlev.maxdiff = params->diff; |
| 3549 | dlev.maxkdiff = params->kdiff; |
| 3550 | if (c == 2 && r == 2) |
| 3551 | dlev.maxdiff = DIFF_BLOCK; |
| 3552 | |
| 3553 | grid = snewn(area, digit); |
| 3554 | locs = snewn(area, struct xy); |
| 3555 | grid2 = snewn(area, digit); |
| 3556 | |
| 3557 | blocks = alloc_block_structure (c, r, area, cr, cr); |
| 3558 | |
| 3559 | kblocks = NULL; |
| 3560 | kgrid = (params->killer) ? snewn(area, digit) : NULL; |
| 3561 | |
| 3562 | #ifdef STANDALONE_SOLVER |
| 3563 | assert(!"This should never happen, so we don't need to create blocknames"); |
| 3564 | #endif |
| 3565 | |
| 3566 | /* |
| 3567 | * Loop until we get a grid of the required difficulty. This is |
| 3568 | * nasty, but it seems to be unpleasantly hard to generate |
| 3569 | * difficult grids otherwise. |
| 3570 | */ |
| 3571 | while (1) { |
| 3572 | /* |
| 3573 | * Generate a random solved state, starting by |
| 3574 | * constructing the block structure. |
| 3575 | */ |
| 3576 | if (r == 1) { /* jigsaw mode */ |
| 3577 | int *dsf = divvy_rectangle(cr, cr, cr, rs); |
| 3578 | |
| 3579 | dsf_to_blocks (dsf, blocks, cr, cr); |
| 3580 | |
| 3581 | sfree(dsf); |
| 3582 | } else { /* basic Sudoku mode */ |
| 3583 | for (y = 0; y < cr; y++) |
| 3584 | for (x = 0; x < cr; x++) |
| 3585 | blocks->whichblock[y*cr+x] = (y/c) * c + (x/r); |
| 3586 | } |
| 3587 | make_blocks_from_whichblock(blocks); |
| 3588 | |
| 3589 | if (params->killer) { |
| 3590 | if (kblocks) free_block_structure(kblocks); |
| 3591 | kblocks = gen_killer_cages(cr, rs, params->kdiff > DIFF_KSINGLE); |
| 3592 | } |
| 3593 | |
| 3594 | if (!gridgen(cr, blocks, kblocks, params->xtype, grid, rs, area*area)) |
| 3595 | continue; |
| 3596 | assert(check_valid(cr, blocks, kblocks, params->xtype, grid)); |
| 3597 | |
| 3598 | /* |
| 3599 | * Save the solved grid in aux. |
| 3600 | */ |
| 3601 | { |
| 3602 | /* |
| 3603 | * We might already have written *aux the last time we |
| 3604 | * went round this loop, in which case we should free |
| 3605 | * the old aux before overwriting it with the new one. |
| 3606 | */ |
| 3607 | if (*aux) { |
| 3608 | sfree(*aux); |
| 3609 | } |
| 3610 | |
| 3611 | *aux = encode_solve_move(cr, grid); |
| 3612 | } |
| 3613 | |
| 3614 | /* |
| 3615 | * Now we have a solved grid. For normal puzzles, we start removing |
| 3616 | * things from it while preserving solubility. Killer puzzles are |
| 3617 | * different: we just pass the empty grid to the solver, and use |
| 3618 | * the puzzle if it comes back solved. |
| 3619 | */ |
| 3620 | |
| 3621 | if (params->killer) { |
| 3622 | struct block_structure *good_cages = NULL; |
| 3623 | struct block_structure *last_cages = NULL; |
| 3624 | int ntries = 0; |
| 3625 | |
| 3626 | memcpy(grid2, grid, area); |
| 3627 | |
| 3628 | for (;;) { |
| 3629 | compute_kclues(kblocks, kgrid, grid2, area); |
| 3630 | |
| 3631 | memset(grid, 0, area * sizeof *grid); |
| 3632 | solver(cr, blocks, kblocks, params->xtype, grid, kgrid, &dlev); |
| 3633 | if (dlev.diff == dlev.maxdiff && dlev.kdiff == dlev.maxkdiff) { |
| 3634 | /* |
| 3635 | * We have one that matches our difficulty. Store it for |
| 3636 | * later, but keep going. |
| 3637 | */ |
| 3638 | if (good_cages) |
| 3639 | free_block_structure(good_cages); |
| 3640 | ntries = 0; |
| 3641 | good_cages = dup_block_structure(kblocks); |
| 3642 | if (!merge_some_cages(kblocks, cr, area, grid2, rs)) |
| 3643 | break; |
| 3644 | } else if (dlev.diff > dlev.maxdiff || dlev.kdiff > dlev.maxkdiff) { |
| 3645 | /* |
| 3646 | * Give up after too many tries and either use the good one we |
| 3647 | * found, or generate a new grid. |
| 3648 | */ |
| 3649 | if (++ntries > 50) |
| 3650 | break; |
| 3651 | /* |
| 3652 | * The difficulty level got too high. If we have a good |
| 3653 | * one, use it, otherwise go back to the last one that |
| 3654 | * was at a lower difficulty and restart the process from |
| 3655 | * there. |
| 3656 | */ |
| 3657 | if (good_cages != NULL) { |
| 3658 | free_block_structure(kblocks); |
| 3659 | kblocks = dup_block_structure(good_cages); |
| 3660 | if (!merge_some_cages(kblocks, cr, area, grid2, rs)) |
| 3661 | break; |
| 3662 | } else { |
| 3663 | if (last_cages == NULL) |
| 3664 | break; |
| 3665 | free_block_structure(kblocks); |
| 3666 | kblocks = last_cages; |
| 3667 | last_cages = NULL; |
| 3668 | } |
| 3669 | } else { |
| 3670 | if (last_cages) |
| 3671 | free_block_structure(last_cages); |
| 3672 | last_cages = dup_block_structure(kblocks); |
| 3673 | if (!merge_some_cages(kblocks, cr, area, grid2, rs)) |
| 3674 | break; |
| 3675 | } |
| 3676 | } |
| 3677 | if (last_cages) |
| 3678 | free_block_structure(last_cages); |
| 3679 | if (good_cages != NULL) { |
| 3680 | free_block_structure(kblocks); |
| 3681 | kblocks = good_cages; |
| 3682 | compute_kclues(kblocks, kgrid, grid2, area); |
| 3683 | memset(grid, 0, area * sizeof *grid); |
| 3684 | break; |
| 3685 | } |
| 3686 | continue; |
| 3687 | } |
| 3688 | |
| 3689 | /* |
| 3690 | * Find the set of equivalence classes of squares permitted |
| 3691 | * by the selected symmetry. We do this by enumerating all |
| 3692 | * the grid squares which have no symmetric companion |
| 3693 | * sorting lower than themselves. |
| 3694 | */ |
| 3695 | nlocs = 0; |
| 3696 | for (y = 0; y < cr; y++) |
| 3697 | for (x = 0; x < cr; x++) { |
| 3698 | int i = y*cr+x; |
| 3699 | int j; |
| 3700 | |
| 3701 | ncoords = symmetries(params, x, y, coords, params->symm); |
| 3702 | for (j = 0; j < ncoords; j++) |
| 3703 | if (coords[2*j+1]*cr+coords[2*j] < i) |
| 3704 | break; |
| 3705 | if (j == ncoords) { |
| 3706 | locs[nlocs].x = x; |
| 3707 | locs[nlocs].y = y; |
| 3708 | nlocs++; |
| 3709 | } |
| 3710 | } |
| 3711 | |
| 3712 | /* |
| 3713 | * Now shuffle that list. |
| 3714 | */ |
| 3715 | shuffle(locs, nlocs, sizeof(*locs), rs); |
| 3716 | |
| 3717 | /* |
| 3718 | * Now loop over the shuffled list and, for each element, |
| 3719 | * see whether removing that element (and its reflections) |
| 3720 | * from the grid will still leave the grid soluble. |
| 3721 | */ |
| 3722 | for (i = 0; i < nlocs; i++) { |
| 3723 | x = locs[i].x; |
| 3724 | y = locs[i].y; |
| 3725 | |
| 3726 | memcpy(grid2, grid, area); |
| 3727 | ncoords = symmetries(params, x, y, coords, params->symm); |
| 3728 | for (j = 0; j < ncoords; j++) |
| 3729 | grid2[coords[2*j+1]*cr+coords[2*j]] = 0; |
| 3730 | |
| 3731 | solver(cr, blocks, kblocks, params->xtype, grid2, kgrid, &dlev); |
| 3732 | if (dlev.diff <= dlev.maxdiff && |
| 3733 | (!params->killer || dlev.kdiff <= dlev.maxkdiff)) { |
| 3734 | for (j = 0; j < ncoords; j++) |
| 3735 | grid[coords[2*j+1]*cr+coords[2*j]] = 0; |
| 3736 | } |
| 3737 | } |
| 3738 | |
| 3739 | memcpy(grid2, grid, area); |
| 3740 | |
| 3741 | solver(cr, blocks, kblocks, params->xtype, grid2, kgrid, &dlev); |
| 3742 | if (dlev.diff == dlev.maxdiff && |
| 3743 | (!params->killer || dlev.kdiff == dlev.maxkdiff)) |
| 3744 | break; /* found one! */ |
| 3745 | } |
| 3746 | |
| 3747 | sfree(grid2); |
| 3748 | sfree(locs); |
| 3749 | |
| 3750 | /* |
| 3751 | * Now we have the grid as it will be presented to the user. |
| 3752 | * Encode it in a game desc. |
| 3753 | */ |
| 3754 | desc = encode_puzzle_desc(params, grid, blocks, kgrid, kblocks); |
| 3755 | |
| 3756 | sfree(grid); |
| 3757 | free_block_structure(blocks); |
| 3758 | if (params->killer) { |
| 3759 | free_block_structure(kblocks); |
| 3760 | sfree(kgrid); |
| 3761 | } |
| 3762 | |
| 3763 | return desc; |
| 3764 | } |
| 3765 | |
| 3766 | static char *spec_to_grid(char *desc, digit *grid, int area) |
| 3767 | { |
| 3768 | int i = 0; |
| 3769 | while (*desc && *desc != ',') { |
| 3770 | int n = *desc++; |
| 3771 | if (n >= 'a' && n <= 'z') { |
| 3772 | int run = n - 'a' + 1; |
| 3773 | assert(i + run <= area); |
| 3774 | while (run-- > 0) |
| 3775 | grid[i++] = 0; |
| 3776 | } else if (n == '_') { |
| 3777 | /* do nothing */; |
| 3778 | } else if (n > '0' && n <= '9') { |
| 3779 | assert(i < area); |
| 3780 | grid[i++] = atoi(desc-1); |
| 3781 | while (*desc >= '0' && *desc <= '9') |
| 3782 | desc++; |
| 3783 | } else { |
| 3784 | assert(!"We can't get here"); |
| 3785 | } |
| 3786 | } |
| 3787 | assert(i == area); |
| 3788 | return desc; |
| 3789 | } |
| 3790 | |
| 3791 | /* |
| 3792 | * Create a DSF from a spec found in *pdesc. Update this to point past the |
| 3793 | * end of the block spec, and return an error string or NULL if everything |
| 3794 | * is OK. The DSF is stored in *PDSF. |
| 3795 | */ |
| 3796 | static char *spec_to_dsf(char **pdesc, int **pdsf, int cr, int area) |
| 3797 | { |
| 3798 | char *desc = *pdesc; |
| 3799 | int pos = 0; |
| 3800 | int *dsf; |
| 3801 | |
| 3802 | *pdsf = dsf = snew_dsf(area); |
| 3803 | |
| 3804 | while (*desc && *desc != ',') { |
| 3805 | int c, adv; |
| 3806 | |
| 3807 | if (*desc == '_') |
| 3808 | c = 0; |
| 3809 | else if (*desc >= 'a' && *desc <= 'z') |
| 3810 | c = *desc - 'a' + 1; |
| 3811 | else { |
| 3812 | sfree(dsf); |
| 3813 | return "Invalid character in game description"; |
| 3814 | } |
| 3815 | desc++; |
| 3816 | |
| 3817 | adv = (c != 25); /* 'z' is a special case */ |
| 3818 | |
| 3819 | while (c-- > 0) { |
| 3820 | int p0, p1; |
| 3821 | |
| 3822 | /* |
| 3823 | * Non-edge; merge the two dsf classes on either |
| 3824 | * side of it. |
| 3825 | */ |
| 3826 | assert(pos < 2*cr*(cr-1)); |
| 3827 | if (pos < cr*(cr-1)) { |
| 3828 | int y = pos/(cr-1); |
| 3829 | int x = pos%(cr-1); |
| 3830 | p0 = y*cr+x; |
| 3831 | p1 = y*cr+x+1; |
| 3832 | } else { |
| 3833 | int x = pos/(cr-1) - cr; |
| 3834 | int y = pos%(cr-1); |
| 3835 | p0 = y*cr+x; |
| 3836 | p1 = (y+1)*cr+x; |
| 3837 | } |
| 3838 | dsf_merge(dsf, p0, p1); |
| 3839 | |
| 3840 | pos++; |
| 3841 | } |
| 3842 | if (adv) |
| 3843 | pos++; |
| 3844 | } |
| 3845 | *pdesc = desc; |
| 3846 | |
| 3847 | /* |
| 3848 | * When desc is exhausted, we expect to have gone exactly |
| 3849 | * one space _past_ the end of the grid, due to the dummy |
| 3850 | * edge at the end. |
| 3851 | */ |
| 3852 | if (pos != 2*cr*(cr-1)+1) { |
| 3853 | sfree(dsf); |
| 3854 | return "Not enough data in block structure specification"; |
| 3855 | } |
| 3856 | |
| 3857 | return NULL; |
| 3858 | } |
| 3859 | |
| 3860 | static char *validate_grid_desc(char **pdesc, int range, int area) |
| 3861 | { |
| 3862 | char *desc = *pdesc; |
| 3863 | int squares = 0; |
| 3864 | while (*desc && *desc != ',') { |
| 3865 | int n = *desc++; |
| 3866 | if (n >= 'a' && n <= 'z') { |
| 3867 | squares += n - 'a' + 1; |
| 3868 | } else if (n == '_') { |
| 3869 | /* do nothing */; |
| 3870 | } else if (n > '0' && n <= '9') { |
| 3871 | int val = atoi(desc-1); |
| 3872 | if (val < 1 || val > range) |
| 3873 | return "Out-of-range number in game description"; |
| 3874 | squares++; |
| 3875 | while (*desc >= '0' && *desc <= '9') |
| 3876 | desc++; |
| 3877 | } else |
| 3878 | return "Invalid character in game description"; |
| 3879 | } |
| 3880 | |
| 3881 | if (squares < area) |
| 3882 | return "Not enough data to fill grid"; |
| 3883 | |
| 3884 | if (squares > area) |
| 3885 | return "Too much data to fit in grid"; |
| 3886 | *pdesc = desc; |
| 3887 | return NULL; |
| 3888 | } |
| 3889 | |
| 3890 | static char *validate_block_desc(char **pdesc, int cr, int area, |
| 3891 | int min_nr_blocks, int max_nr_blocks, |
| 3892 | int min_nr_squares, int max_nr_squares) |
| 3893 | { |
| 3894 | char *err; |
| 3895 | int *dsf; |
| 3896 | |
| 3897 | err = spec_to_dsf(pdesc, &dsf, cr, area); |
| 3898 | if (err) { |
| 3899 | return err; |
| 3900 | } |
| 3901 | |
| 3902 | if (min_nr_squares == max_nr_squares) { |
| 3903 | assert(min_nr_blocks == max_nr_blocks); |
| 3904 | assert(min_nr_blocks * min_nr_squares == area); |
| 3905 | } |
| 3906 | /* |
| 3907 | * Now we've got our dsf. Verify that it matches |
| 3908 | * expectations. |
| 3909 | */ |
| 3910 | { |
| 3911 | int *canons, *counts; |
| 3912 | int i, j, c, ncanons = 0; |
| 3913 | |
| 3914 | canons = snewn(max_nr_blocks, int); |
| 3915 | counts = snewn(max_nr_blocks, int); |
| 3916 | |
| 3917 | for (i = 0; i < area; i++) { |
| 3918 | j = dsf_canonify(dsf, i); |
| 3919 | |
| 3920 | for (c = 0; c < ncanons; c++) |
| 3921 | if (canons[c] == j) { |
| 3922 | counts[c]++; |
| 3923 | if (counts[c] > max_nr_squares) { |
| 3924 | sfree(dsf); |
| 3925 | sfree(canons); |
| 3926 | sfree(counts); |
| 3927 | return "A jigsaw block is too big"; |
| 3928 | } |
| 3929 | break; |
| 3930 | } |
| 3931 | |
| 3932 | if (c == ncanons) { |
| 3933 | if (ncanons >= max_nr_blocks) { |
| 3934 | sfree(dsf); |
| 3935 | sfree(canons); |
| 3936 | sfree(counts); |
| 3937 | return "Too many distinct jigsaw blocks"; |
| 3938 | } |
| 3939 | canons[ncanons] = j; |
| 3940 | counts[ncanons] = 1; |
| 3941 | ncanons++; |
| 3942 | } |
| 3943 | } |
| 3944 | |
| 3945 | if (ncanons < min_nr_blocks) { |
| 3946 | sfree(dsf); |
| 3947 | sfree(canons); |
| 3948 | sfree(counts); |
| 3949 | return "Not enough distinct jigsaw blocks"; |
| 3950 | } |
| 3951 | for (c = 0; c < ncanons; c++) { |
| 3952 | if (counts[c] < min_nr_squares) { |
| 3953 | sfree(dsf); |
| 3954 | sfree(canons); |
| 3955 | sfree(counts); |
| 3956 | return "A jigsaw block is too small"; |
| 3957 | } |
| 3958 | } |
| 3959 | sfree(canons); |
| 3960 | sfree(counts); |
| 3961 | } |
| 3962 | |
| 3963 | sfree(dsf); |
| 3964 | return NULL; |
| 3965 | } |
| 3966 | |
| 3967 | static char *validate_desc(game_params *params, char *desc) |
| 3968 | { |
| 3969 | int cr = params->c * params->r, area = cr*cr; |
| 3970 | char *err; |
| 3971 | |
| 3972 | err = validate_grid_desc(&desc, cr, area); |
| 3973 | if (err) |
| 3974 | return err; |
| 3975 | |
| 3976 | if (params->r == 1) { |
| 3977 | /* |
| 3978 | * Now we expect a suffix giving the jigsaw block |
| 3979 | * structure. Parse it and validate that it divides the |
| 3980 | * grid into the right number of regions which are the |
| 3981 | * right size. |
| 3982 | */ |
| 3983 | if (*desc != ',') |
| 3984 | return "Expected jigsaw block structure in game description"; |
| 3985 | desc++; |
| 3986 | err = validate_block_desc(&desc, cr, area, cr, cr, cr, cr); |
| 3987 | if (err) |
| 3988 | return err; |
| 3989 | |
| 3990 | } |
| 3991 | if (params->killer) { |
| 3992 | if (*desc != ',') |
| 3993 | return "Expected killer block structure in game description"; |
| 3994 | desc++; |
| 3995 | err = validate_block_desc(&desc, cr, area, cr, area, 2, cr); |
| 3996 | if (err) |
| 3997 | return err; |
| 3998 | if (*desc != ',') |
| 3999 | return "Expected killer clue grid in game description"; |
| 4000 | desc++; |
| 4001 | err = validate_grid_desc(&desc, cr * area, area); |
| 4002 | if (err) |
| 4003 | return err; |
| 4004 | } |
| 4005 | if (*desc) |
| 4006 | return "Unexpected data at end of game description"; |
| 4007 | |
| 4008 | return NULL; |
| 4009 | } |
| 4010 | |
| 4011 | static game_state *new_game(midend *me, game_params *params, char *desc) |
| 4012 | { |
| 4013 | game_state *state = snew(game_state); |
| 4014 | int c = params->c, r = params->r, cr = c*r, area = cr * cr; |
| 4015 | int i; |
| 4016 | |
| 4017 | precompute_sum_bits(); |
| 4018 | |
| 4019 | state->cr = cr; |
| 4020 | state->xtype = params->xtype; |
| 4021 | state->killer = params->killer; |
| 4022 | |
| 4023 | state->grid = snewn(area, digit); |
| 4024 | state->pencil = snewn(area * cr, unsigned char); |
| 4025 | memset(state->pencil, 0, area * cr); |
| 4026 | state->immutable = snewn(area, unsigned char); |
| 4027 | memset(state->immutable, FALSE, area); |
| 4028 | |
| 4029 | state->blocks = alloc_block_structure (c, r, area, cr, cr); |
| 4030 | |
| 4031 | if (params->killer) { |
| 4032 | state->kblocks = alloc_block_structure (c, r, area, cr, area); |
| 4033 | state->kgrid = snewn(area, digit); |
| 4034 | } else { |
| 4035 | state->kblocks = NULL; |
| 4036 | state->kgrid = NULL; |
| 4037 | } |
| 4038 | state->completed = state->cheated = FALSE; |
| 4039 | |
| 4040 | desc = spec_to_grid(desc, state->grid, area); |
| 4041 | for (i = 0; i < area; i++) |
| 4042 | if (state->grid[i] != 0) |
| 4043 | state->immutable[i] = TRUE; |
| 4044 | |
| 4045 | if (r == 1) { |
| 4046 | char *err; |
| 4047 | int *dsf; |
| 4048 | assert(*desc == ','); |
| 4049 | desc++; |
| 4050 | err = spec_to_dsf(&desc, &dsf, cr, area); |
| 4051 | assert(err == NULL); |
| 4052 | dsf_to_blocks(dsf, state->blocks, cr, cr); |
| 4053 | sfree(dsf); |
| 4054 | } else { |
| 4055 | int x, y; |
| 4056 | |
| 4057 | for (y = 0; y < cr; y++) |
| 4058 | for (x = 0; x < cr; x++) |
| 4059 | state->blocks->whichblock[y*cr+x] = (y/c) * c + (x/r); |
| 4060 | } |
| 4061 | make_blocks_from_whichblock(state->blocks); |
| 4062 | |
| 4063 | if (params->killer) { |
| 4064 | char *err; |
| 4065 | int *dsf; |
| 4066 | assert(*desc == ','); |
| 4067 | desc++; |
| 4068 | err = spec_to_dsf(&desc, &dsf, cr, area); |
| 4069 | assert(err == NULL); |
| 4070 | dsf_to_blocks(dsf, state->kblocks, cr, area); |
| 4071 | sfree(dsf); |
| 4072 | make_blocks_from_whichblock(state->kblocks); |
| 4073 | |
| 4074 | assert(*desc == ','); |
| 4075 | desc++; |
| 4076 | desc = spec_to_grid(desc, state->kgrid, area); |
| 4077 | } |
| 4078 | assert(!*desc); |
| 4079 | |
| 4080 | #ifdef STANDALONE_SOLVER |
| 4081 | /* |
| 4082 | * Set up the block names for solver diagnostic output. |
| 4083 | */ |
| 4084 | { |
| 4085 | char *p = (char *)(state->blocks->blocknames + cr); |
| 4086 | |
| 4087 | if (r == 1) { |
| 4088 | for (i = 0; i < area; i++) { |
| 4089 | int j = state->blocks->whichblock[i]; |
| 4090 | if (!state->blocks->blocknames[j]) { |
| 4091 | state->blocks->blocknames[j] = p; |
| 4092 | p += 1 + sprintf(p, "starting at (%d,%d)", |
| 4093 | 1 + i%cr, 1 + i/cr); |
| 4094 | } |
| 4095 | } |
| 4096 | } else { |
| 4097 | int bx, by; |
| 4098 | for (by = 0; by < r; by++) |
| 4099 | for (bx = 0; bx < c; bx++) { |
| 4100 | state->blocks->blocknames[by*c+bx] = p; |
| 4101 | p += 1 + sprintf(p, "(%d,%d)", bx+1, by+1); |
| 4102 | } |
| 4103 | } |
| 4104 | assert(p - (char *)state->blocks->blocknames < (int)(cr*(sizeof(char *)+80))); |
| 4105 | for (i = 0; i < cr; i++) |
| 4106 | assert(state->blocks->blocknames[i]); |
| 4107 | } |
| 4108 | #endif |
| 4109 | |
| 4110 | return state; |
| 4111 | } |
| 4112 | |
| 4113 | static game_state *dup_game(game_state *state) |
| 4114 | { |
| 4115 | game_state *ret = snew(game_state); |
| 4116 | int cr = state->cr, area = cr * cr; |
| 4117 | |
| 4118 | ret->cr = state->cr; |
| 4119 | ret->xtype = state->xtype; |
| 4120 | ret->killer = state->killer; |
| 4121 | |
| 4122 | ret->blocks = state->blocks; |
| 4123 | ret->blocks->refcount++; |
| 4124 | |
| 4125 | ret->kblocks = state->kblocks; |
| 4126 | if (ret->kblocks) |
| 4127 | ret->kblocks->refcount++; |
| 4128 | |
| 4129 | ret->grid = snewn(area, digit); |
| 4130 | memcpy(ret->grid, state->grid, area); |
| 4131 | |
| 4132 | if (state->killer) { |
| 4133 | ret->kgrid = snewn(area, digit); |
| 4134 | memcpy(ret->kgrid, state->kgrid, area); |
| 4135 | } else |
| 4136 | ret->kgrid = NULL; |
| 4137 | |
| 4138 | ret->pencil = snewn(area * cr, unsigned char); |
| 4139 | memcpy(ret->pencil, state->pencil, area * cr); |
| 4140 | |
| 4141 | ret->immutable = snewn(area, unsigned char); |
| 4142 | memcpy(ret->immutable, state->immutable, area); |
| 4143 | |
| 4144 | ret->completed = state->completed; |
| 4145 | ret->cheated = state->cheated; |
| 4146 | |
| 4147 | return ret; |
| 4148 | } |
| 4149 | |
| 4150 | static void free_game(game_state *state) |
| 4151 | { |
| 4152 | free_block_structure(state->blocks); |
| 4153 | if (state->kblocks) |
| 4154 | free_block_structure(state->kblocks); |
| 4155 | |
| 4156 | sfree(state->immutable); |
| 4157 | sfree(state->pencil); |
| 4158 | sfree(state->grid); |
| 4159 | if (state->kgrid) sfree(state->kgrid); |
| 4160 | sfree(state); |
| 4161 | } |
| 4162 | |
| 4163 | static char *solve_game(game_state *state, game_state *currstate, |
| 4164 | char *ai, char **error) |
| 4165 | { |
| 4166 | int cr = state->cr; |
| 4167 | char *ret; |
| 4168 | digit *grid; |
| 4169 | struct difficulty dlev; |
| 4170 | |
| 4171 | /* |
| 4172 | * If we already have the solution in ai, save ourselves some |
| 4173 | * time. |
| 4174 | */ |
| 4175 | if (ai) |
| 4176 | return dupstr(ai); |
| 4177 | |
| 4178 | grid = snewn(cr*cr, digit); |
| 4179 | memcpy(grid, state->grid, cr*cr); |
| 4180 | dlev.maxdiff = DIFF_RECURSIVE; |
| 4181 | dlev.maxkdiff = DIFF_KINTERSECT; |
| 4182 | solver(cr, state->blocks, state->kblocks, state->xtype, grid, |
| 4183 | state->kgrid, &dlev); |
| 4184 | |
| 4185 | *error = NULL; |
| 4186 | |
| 4187 | if (dlev.diff == DIFF_IMPOSSIBLE) |
| 4188 | *error = "No solution exists for this puzzle"; |
| 4189 | else if (dlev.diff == DIFF_AMBIGUOUS) |
| 4190 | *error = "Multiple solutions exist for this puzzle"; |
| 4191 | |
| 4192 | if (*error) { |
| 4193 | sfree(grid); |
| 4194 | return NULL; |
| 4195 | } |
| 4196 | |
| 4197 | ret = encode_solve_move(cr, grid); |
| 4198 | |
| 4199 | sfree(grid); |
| 4200 | |
| 4201 | return ret; |
| 4202 | } |
| 4203 | |
| 4204 | static char *grid_text_format(int cr, struct block_structure *blocks, |
| 4205 | int xtype, digit *grid) |
| 4206 | { |
| 4207 | int vmod, hmod; |
| 4208 | int x, y; |
| 4209 | int totallen, linelen, nlines; |
| 4210 | char *ret, *p, ch; |
| 4211 | |
| 4212 | /* |
| 4213 | * For non-jigsaw Sudoku, we format in the way we always have, |
| 4214 | * by having the digits unevenly spaced so that the dividing |
| 4215 | * lines can fit in: |
| 4216 | * |
| 4217 | * . . | . . |
| 4218 | * . . | . . |
| 4219 | * ----+---- |
| 4220 | * . . | . . |
| 4221 | * . . | . . |
| 4222 | * |
| 4223 | * For jigsaw puzzles, however, we must leave space between |
| 4224 | * _all_ pairs of digits for an optional dividing line, so we |
| 4225 | * have to move to the rather ugly |
| 4226 | * |
| 4227 | * . . . . |
| 4228 | * ------+------ |
| 4229 | * . . | . . |
| 4230 | * +---+ |
| 4231 | * . . | . | . |
| 4232 | * ------+ | |
| 4233 | * . . . | . |
| 4234 | * |
| 4235 | * We deal with both cases using the same formatting code; we |
| 4236 | * simply invent a vmod value such that there's a vertical |
| 4237 | * dividing line before column i iff i is divisible by vmod |
| 4238 | * (so it's r in the first case and 1 in the second), and hmod |
| 4239 | * likewise for horizontal dividing lines. |
| 4240 | */ |
| 4241 | |
| 4242 | if (blocks->r != 1) { |
| 4243 | vmod = blocks->r; |
| 4244 | hmod = blocks->c; |
| 4245 | } else { |
| 4246 | vmod = hmod = 1; |
| 4247 | } |
| 4248 | |
| 4249 | /* |
| 4250 | * Line length: we have cr digits, each with a space after it, |
| 4251 | * and (cr-1)/vmod dividing lines, each with a space after it. |
| 4252 | * The final space is replaced by a newline, but that doesn't |
| 4253 | * affect the length. |
| 4254 | */ |
| 4255 | linelen = 2*(cr + (cr-1)/vmod); |
| 4256 | |
| 4257 | /* |
| 4258 | * Number of lines: we have cr rows of digits, and (cr-1)/hmod |
| 4259 | * dividing rows. |
| 4260 | */ |
| 4261 | nlines = cr + (cr-1)/hmod; |
| 4262 | |
| 4263 | /* |
| 4264 | * Allocate the space. |
| 4265 | */ |
| 4266 | totallen = linelen * nlines; |
| 4267 | ret = snewn(totallen+1, char); /* leave room for terminating NUL */ |
| 4268 | |
| 4269 | /* |
| 4270 | * Write the text. |
| 4271 | */ |
| 4272 | p = ret; |
| 4273 | for (y = 0; y < cr; y++) { |
| 4274 | /* |
| 4275 | * Row of digits. |
| 4276 | */ |
| 4277 | for (x = 0; x < cr; x++) { |
| 4278 | /* |
| 4279 | * Digit. |
| 4280 | */ |
| 4281 | digit d = grid[y*cr+x]; |
| 4282 | |
| 4283 | if (d == 0) { |
| 4284 | /* |
| 4285 | * Empty space: we usually write a dot, but we'll |
| 4286 | * highlight spaces on the X-diagonals (in X mode) |
| 4287 | * by using underscores instead. |
| 4288 | */ |
| 4289 | if (xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x))) |
| 4290 | ch = '_'; |
| 4291 | else |
| 4292 | ch = '.'; |
| 4293 | } else if (d <= 9) { |
| 4294 | ch = '0' + d; |
| 4295 | } else { |
| 4296 | ch = 'a' + d-10; |
| 4297 | } |
| 4298 | |
| 4299 | *p++ = ch; |
| 4300 | if (x == cr-1) { |
| 4301 | *p++ = '\n'; |
| 4302 | continue; |
| 4303 | } |
| 4304 | *p++ = ' '; |
| 4305 | |
| 4306 | if ((x+1) % vmod) |
| 4307 | continue; |
| 4308 | |
| 4309 | /* |
| 4310 | * Optional dividing line. |
| 4311 | */ |
| 4312 | if (blocks->whichblock[y*cr+x] != blocks->whichblock[y*cr+x+1]) |
| 4313 | ch = '|'; |
| 4314 | else |
| 4315 | ch = ' '; |
| 4316 | *p++ = ch; |
| 4317 | *p++ = ' '; |
| 4318 | } |
| 4319 | if (y == cr-1 || (y+1) % hmod) |
| 4320 | continue; |
| 4321 | |
| 4322 | /* |
| 4323 | * Dividing row. |
| 4324 | */ |
| 4325 | for (x = 0; x < cr; x++) { |
| 4326 | int dwid; |
| 4327 | int tl, tr, bl, br; |
| 4328 | |
| 4329 | /* |
| 4330 | * Division between two squares. This varies |
| 4331 | * complicatedly in length. |
| 4332 | */ |
| 4333 | dwid = 2; /* digit and its following space */ |
| 4334 | if (x == cr-1) |
| 4335 | dwid--; /* no following space at end of line */ |
| 4336 | if (x > 0 && x % vmod == 0) |
| 4337 | dwid++; /* preceding space after a divider */ |
| 4338 | |
| 4339 | if (blocks->whichblock[y*cr+x] != blocks->whichblock[(y+1)*cr+x]) |
| 4340 | ch = '-'; |
| 4341 | else |
| 4342 | ch = ' '; |
| 4343 | |
| 4344 | while (dwid-- > 0) |
| 4345 | *p++ = ch; |
| 4346 | |
| 4347 | if (x == cr-1) { |
| 4348 | *p++ = '\n'; |
| 4349 | break; |
| 4350 | } |
| 4351 | |
| 4352 | if ((x+1) % vmod) |
| 4353 | continue; |
| 4354 | |
| 4355 | /* |
| 4356 | * Corner square. This is: |
| 4357 | * - a space if all four surrounding squares are in |
| 4358 | * the same block |
| 4359 | * - a vertical line if the two left ones are in one |
| 4360 | * block and the two right in another |
| 4361 | * - a horizontal line if the two top ones are in one |
| 4362 | * block and the two bottom in another |
| 4363 | * - a plus sign in all other cases. (If we had a |
| 4364 | * richer character set available we could break |
| 4365 | * this case up further by doing fun things with |
| 4366 | * line-drawing T-pieces.) |
| 4367 | */ |
| 4368 | tl = blocks->whichblock[y*cr+x]; |
| 4369 | tr = blocks->whichblock[y*cr+x+1]; |
| 4370 | bl = blocks->whichblock[(y+1)*cr+x]; |
| 4371 | br = blocks->whichblock[(y+1)*cr+x+1]; |
| 4372 | |
| 4373 | if (tl == tr && tr == bl && bl == br) |
| 4374 | ch = ' '; |
| 4375 | else if (tl == bl && tr == br) |
| 4376 | ch = '|'; |
| 4377 | else if (tl == tr && bl == br) |
| 4378 | ch = '-'; |
| 4379 | else |
| 4380 | ch = '+'; |
| 4381 | |
| 4382 | *p++ = ch; |
| 4383 | } |
| 4384 | } |
| 4385 | |
| 4386 | assert(p - ret == totallen); |
| 4387 | *p = '\0'; |
| 4388 | return ret; |
| 4389 | } |
| 4390 | |
| 4391 | static int game_can_format_as_text_now(game_params *params) |
| 4392 | { |
| 4393 | /* |
| 4394 | * Formatting Killer puzzles as text is currently unsupported. I |
| 4395 | * can't think of any sensible way of doing it which doesn't |
| 4396 | * involve expanding the puzzle to such a large scale as to make |
| 4397 | * it unusable. |
| 4398 | */ |
| 4399 | if (params->killer) |
| 4400 | return FALSE; |
| 4401 | return TRUE; |
| 4402 | } |
| 4403 | |
| 4404 | static char *game_text_format(game_state *state) |
| 4405 | { |
| 4406 | assert(!state->kblocks); |
| 4407 | return grid_text_format(state->cr, state->blocks, state->xtype, |
| 4408 | state->grid); |
| 4409 | } |
| 4410 | |
| 4411 | struct game_ui { |
| 4412 | /* |
| 4413 | * These are the coordinates of the currently highlighted |
| 4414 | * square on the grid, if hshow = 1. |
| 4415 | */ |
| 4416 | int hx, hy; |
| 4417 | /* |
| 4418 | * This indicates whether the current highlight is a |
| 4419 | * pencil-mark one or a real one. |
| 4420 | */ |
| 4421 | int hpencil; |
| 4422 | /* |
| 4423 | * This indicates whether or not we're showing the highlight |
| 4424 | * (used to be hx = hy = -1); important so that when we're |
| 4425 | * using the cursor keys it doesn't keep coming back at a |
| 4426 | * fixed position. When hshow = 1, pressing a valid number |
| 4427 | * or letter key or Space will enter that number or letter in the grid. |
| 4428 | */ |
| 4429 | int hshow; |
| 4430 | /* |
| 4431 | * This indicates whether we're using the highlight as a cursor; |
| 4432 | * it means that it doesn't vanish on a keypress, and that it is |
| 4433 | * allowed on immutable squares. |
| 4434 | */ |
| 4435 | int hcursor; |
| 4436 | }; |
| 4437 | |
| 4438 | static game_ui *new_ui(game_state *state) |
| 4439 | { |
| 4440 | game_ui *ui = snew(game_ui); |
| 4441 | |
| 4442 | ui->hx = ui->hy = 0; |
| 4443 | ui->hpencil = ui->hshow = ui->hcursor = 0; |
| 4444 | |
| 4445 | return ui; |
| 4446 | } |
| 4447 | |
| 4448 | static void free_ui(game_ui *ui) |
| 4449 | { |
| 4450 | sfree(ui); |
| 4451 | } |
| 4452 | |
| 4453 | static char *encode_ui(game_ui *ui) |
| 4454 | { |
| 4455 | return NULL; |
| 4456 | } |
| 4457 | |
| 4458 | static void decode_ui(game_ui *ui, char *encoding) |
| 4459 | { |
| 4460 | } |
| 4461 | |
| 4462 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
| 4463 | game_state *newstate) |
| 4464 | { |
| 4465 | int cr = newstate->cr; |
| 4466 | /* |
| 4467 | * We prevent pencil-mode highlighting of a filled square, unless |
| 4468 | * we're using the cursor keys. So if the user has just filled in |
| 4469 | * a square which we had a pencil-mode highlight in (by Undo, or |
| 4470 | * by Redo, or by Solve), then we cancel the highlight. |
| 4471 | */ |
| 4472 | if (ui->hshow && ui->hpencil && !ui->hcursor && |
| 4473 | newstate->grid[ui->hy * cr + ui->hx] != 0) { |
| 4474 | ui->hshow = 0; |
| 4475 | } |
| 4476 | } |
| 4477 | |
| 4478 | struct game_drawstate { |
| 4479 | int started; |
| 4480 | int cr, xtype; |
| 4481 | int tilesize; |
| 4482 | digit *grid; |
| 4483 | unsigned char *pencil; |
| 4484 | unsigned char *hl; |
| 4485 | /* This is scratch space used within a single call to game_redraw. */ |
| 4486 | int nregions, *entered_items; |
| 4487 | }; |
| 4488 | |
| 4489 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
| 4490 | int x, int y, int button) |
| 4491 | { |
| 4492 | int cr = state->cr; |
| 4493 | int tx, ty; |
| 4494 | char buf[80]; |
| 4495 | |
| 4496 | button &= ~MOD_MASK; |
| 4497 | |
| 4498 | tx = (x + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
| 4499 | ty = (y + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
| 4500 | |
| 4501 | if (tx >= 0 && tx < cr && ty >= 0 && ty < cr) { |
| 4502 | if (button == LEFT_BUTTON) { |
| 4503 | if (state->immutable[ty*cr+tx]) { |
| 4504 | ui->hshow = 0; |
| 4505 | } else if (tx == ui->hx && ty == ui->hy && |
| 4506 | ui->hshow && ui->hpencil == 0) { |
| 4507 | ui->hshow = 0; |
| 4508 | } else { |
| 4509 | ui->hx = tx; |
| 4510 | ui->hy = ty; |
| 4511 | ui->hshow = 1; |
| 4512 | ui->hpencil = 0; |
| 4513 | } |
| 4514 | ui->hcursor = 0; |
| 4515 | return ""; /* UI activity occurred */ |
| 4516 | } |
| 4517 | if (button == RIGHT_BUTTON) { |
| 4518 | /* |
| 4519 | * Pencil-mode highlighting for non filled squares. |
| 4520 | */ |
| 4521 | if (state->grid[ty*cr+tx] == 0) { |
| 4522 | if (tx == ui->hx && ty == ui->hy && |
| 4523 | ui->hshow && ui->hpencil) { |
| 4524 | ui->hshow = 0; |
| 4525 | } else { |
| 4526 | ui->hpencil = 1; |
| 4527 | ui->hx = tx; |
| 4528 | ui->hy = ty; |
| 4529 | ui->hshow = 1; |
| 4530 | } |
| 4531 | } else { |
| 4532 | ui->hshow = 0; |
| 4533 | } |
| 4534 | ui->hcursor = 0; |
| 4535 | return ""; /* UI activity occurred */ |
| 4536 | } |
| 4537 | } |
| 4538 | if (IS_CURSOR_MOVE(button)) { |
| 4539 | move_cursor(button, &ui->hx, &ui->hy, cr, cr, 0); |
| 4540 | ui->hshow = ui->hcursor = 1; |
| 4541 | return ""; |
| 4542 | } |
| 4543 | if (ui->hshow && |
| 4544 | (button == CURSOR_SELECT)) { |
| 4545 | ui->hpencil = 1 - ui->hpencil; |
| 4546 | ui->hcursor = 1; |
| 4547 | return ""; |
| 4548 | } |
| 4549 | |
| 4550 | if (ui->hshow && |
| 4551 | ((button >= '0' && button <= '9' && button - '0' <= cr) || |
| 4552 | (button >= 'a' && button <= 'z' && button - 'a' + 10 <= cr) || |
| 4553 | (button >= 'A' && button <= 'Z' && button - 'A' + 10 <= cr) || |
| 4554 | button == CURSOR_SELECT2 || button == '\b')) { |
| 4555 | int n = button - '0'; |
| 4556 | if (button >= 'A' && button <= 'Z') |
| 4557 | n = button - 'A' + 10; |
| 4558 | if (button >= 'a' && button <= 'z') |
| 4559 | n = button - 'a' + 10; |
| 4560 | if (button == CURSOR_SELECT2 || button == '\b') |
| 4561 | n = 0; |
| 4562 | |
| 4563 | /* |
| 4564 | * Can't overwrite this square. This can only happen here |
| 4565 | * if we're using the cursor keys. |
| 4566 | */ |
| 4567 | if (state->immutable[ui->hy*cr+ui->hx]) |
| 4568 | return NULL; |
| 4569 | |
| 4570 | /* |
| 4571 | * Can't make pencil marks in a filled square. Again, this |
| 4572 | * can only become highlighted if we're using cursor keys. |
| 4573 | */ |
| 4574 | if (ui->hpencil && state->grid[ui->hy*cr+ui->hx]) |
| 4575 | return NULL; |
| 4576 | |
| 4577 | sprintf(buf, "%c%d,%d,%d", |
| 4578 | (char)(ui->hpencil && n > 0 ? 'P' : 'R'), ui->hx, ui->hy, n); |
| 4579 | |
| 4580 | if (!ui->hcursor) ui->hshow = 0; |
| 4581 | |
| 4582 | return dupstr(buf); |
| 4583 | } |
| 4584 | |
| 4585 | return NULL; |
| 4586 | } |
| 4587 | |
| 4588 | static game_state *execute_move(game_state *from, char *move) |
| 4589 | { |
| 4590 | int cr = from->cr; |
| 4591 | game_state *ret; |
| 4592 | int x, y, n; |
| 4593 | |
| 4594 | if (move[0] == 'S') { |
| 4595 | char *p; |
| 4596 | |
| 4597 | ret = dup_game(from); |
| 4598 | ret->completed = ret->cheated = TRUE; |
| 4599 | |
| 4600 | p = move+1; |
| 4601 | for (n = 0; n < cr*cr; n++) { |
| 4602 | ret->grid[n] = atoi(p); |
| 4603 | |
| 4604 | if (!*p || ret->grid[n] < 1 || ret->grid[n] > cr) { |
| 4605 | free_game(ret); |
| 4606 | return NULL; |
| 4607 | } |
| 4608 | |
| 4609 | while (*p && isdigit((unsigned char)*p)) p++; |
| 4610 | if (*p == ',') p++; |
| 4611 | } |
| 4612 | |
| 4613 | return ret; |
| 4614 | } else if ((move[0] == 'P' || move[0] == 'R') && |
| 4615 | sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 && |
| 4616 | x >= 0 && x < cr && y >= 0 && y < cr && n >= 0 && n <= cr) { |
| 4617 | |
| 4618 | ret = dup_game(from); |
| 4619 | if (move[0] == 'P' && n > 0) { |
| 4620 | int index = (y*cr+x) * cr + (n-1); |
| 4621 | ret->pencil[index] = !ret->pencil[index]; |
| 4622 | } else { |
| 4623 | ret->grid[y*cr+x] = n; |
| 4624 | memset(ret->pencil + (y*cr+x)*cr, 0, cr); |
| 4625 | |
| 4626 | /* |
| 4627 | * We've made a real change to the grid. Check to see |
| 4628 | * if the game has been completed. |
| 4629 | */ |
| 4630 | if (!ret->completed && check_valid(cr, ret->blocks, ret->kblocks, |
| 4631 | ret->xtype, ret->grid)) { |
| 4632 | ret->completed = TRUE; |
| 4633 | } |
| 4634 | } |
| 4635 | return ret; |
| 4636 | } else |
| 4637 | return NULL; /* couldn't parse move string */ |
| 4638 | } |
| 4639 | |
| 4640 | /* ---------------------------------------------------------------------- |
| 4641 | * Drawing routines. |
| 4642 | */ |
| 4643 | |
| 4644 | #define SIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) |
| 4645 | #define GETTILESIZE(cr, w) ( (double)(w-1) / (double)(cr+1) ) |
| 4646 | |
| 4647 | static void game_compute_size(game_params *params, int tilesize, |
| 4648 | int *x, int *y) |
| 4649 | { |
| 4650 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
| 4651 | struct { int tilesize; } ads, *ds = &ads; |
| 4652 | ads.tilesize = tilesize; |
| 4653 | |
| 4654 | *x = SIZE(params->c * params->r); |
| 4655 | *y = SIZE(params->c * params->r); |
| 4656 | } |
| 4657 | |
| 4658 | static void game_set_size(drawing *dr, game_drawstate *ds, |
| 4659 | game_params *params, int tilesize) |
| 4660 | { |
| 4661 | ds->tilesize = tilesize; |
| 4662 | } |
| 4663 | |
| 4664 | static float *game_colours(frontend *fe, int *ncolours) |
| 4665 | { |
| 4666 | float *ret = snewn(3 * NCOLOURS, float); |
| 4667 | |
| 4668 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
| 4669 | |
| 4670 | ret[COL_XDIAGONALS * 3 + 0] = 0.9F * ret[COL_BACKGROUND * 3 + 0]; |
| 4671 | ret[COL_XDIAGONALS * 3 + 1] = 0.9F * ret[COL_BACKGROUND * 3 + 1]; |
| 4672 | ret[COL_XDIAGONALS * 3 + 2] = 0.9F * ret[COL_BACKGROUND * 3 + 2]; |
| 4673 | |
| 4674 | ret[COL_GRID * 3 + 0] = 0.0F; |
| 4675 | ret[COL_GRID * 3 + 1] = 0.0F; |
| 4676 | ret[COL_GRID * 3 + 2] = 0.0F; |
| 4677 | |
| 4678 | ret[COL_CLUE * 3 + 0] = 0.0F; |
| 4679 | ret[COL_CLUE * 3 + 1] = 0.0F; |
| 4680 | ret[COL_CLUE * 3 + 2] = 0.0F; |
| 4681 | |
| 4682 | ret[COL_USER * 3 + 0] = 0.0F; |
| 4683 | ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1]; |
| 4684 | ret[COL_USER * 3 + 2] = 0.0F; |
| 4685 | |
| 4686 | ret[COL_HIGHLIGHT * 3 + 0] = 0.78F * ret[COL_BACKGROUND * 3 + 0]; |
| 4687 | ret[COL_HIGHLIGHT * 3 + 1] = 0.78F * ret[COL_BACKGROUND * 3 + 1]; |
| 4688 | ret[COL_HIGHLIGHT * 3 + 2] = 0.78F * ret[COL_BACKGROUND * 3 + 2]; |
| 4689 | |
| 4690 | ret[COL_ERROR * 3 + 0] = 1.0F; |
| 4691 | ret[COL_ERROR * 3 + 1] = 0.0F; |
| 4692 | ret[COL_ERROR * 3 + 2] = 0.0F; |
| 4693 | |
| 4694 | ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; |
| 4695 | ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; |
| 4696 | ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2]; |
| 4697 | |
| 4698 | ret[COL_KILLER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; |
| 4699 | ret[COL_KILLER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; |
| 4700 | ret[COL_KILLER * 3 + 2] = 0.1F * ret[COL_BACKGROUND * 3 + 2]; |
| 4701 | |
| 4702 | *ncolours = NCOLOURS; |
| 4703 | return ret; |
| 4704 | } |
| 4705 | |
| 4706 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
| 4707 | { |
| 4708 | struct game_drawstate *ds = snew(struct game_drawstate); |
| 4709 | int cr = state->cr; |
| 4710 | |
| 4711 | ds->started = FALSE; |
| 4712 | ds->cr = cr; |
| 4713 | ds->xtype = state->xtype; |
| 4714 | ds->grid = snewn(cr*cr, digit); |
| 4715 | memset(ds->grid, cr+2, cr*cr); |
| 4716 | ds->pencil = snewn(cr*cr*cr, digit); |
| 4717 | memset(ds->pencil, 0, cr*cr*cr); |
| 4718 | ds->hl = snewn(cr*cr, unsigned char); |
| 4719 | memset(ds->hl, 0, cr*cr); |
| 4720 | /* |
| 4721 | * ds->entered_items needs one row of cr entries per entity in |
| 4722 | * which digits may not be duplicated. That's one for each row, |
| 4723 | * each column, each block, each diagonal, and each Killer cage. |
| 4724 | */ |
| 4725 | ds->nregions = cr*3 + 2; |
| 4726 | if (state->kblocks) |
| 4727 | ds->nregions += state->kblocks->nr_blocks; |
| 4728 | ds->entered_items = snewn(cr * ds->nregions, int); |
| 4729 | ds->tilesize = 0; /* not decided yet */ |
| 4730 | return ds; |
| 4731 | } |
| 4732 | |
| 4733 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
| 4734 | { |
| 4735 | sfree(ds->hl); |
| 4736 | sfree(ds->pencil); |
| 4737 | sfree(ds->grid); |
| 4738 | sfree(ds->entered_items); |
| 4739 | sfree(ds); |
| 4740 | } |
| 4741 | |
| 4742 | static void draw_number(drawing *dr, game_drawstate *ds, game_state *state, |
| 4743 | int x, int y, int hl) |
| 4744 | { |
| 4745 | int cr = state->cr; |
| 4746 | int tx, ty, tw, th; |
| 4747 | int cx, cy, cw, ch; |
| 4748 | int col_killer = (hl & 32 ? COL_ERROR : COL_KILLER); |
| 4749 | char str[20]; |
| 4750 | |
| 4751 | if (ds->grid[y*cr+x] == state->grid[y*cr+x] && |
| 4752 | ds->hl[y*cr+x] == hl && |
| 4753 | !memcmp(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr)) |
| 4754 | return; /* no change required */ |
| 4755 | |
| 4756 | tx = BORDER + x * TILE_SIZE + 1 + GRIDEXTRA; |
| 4757 | ty = BORDER + y * TILE_SIZE + 1 + GRIDEXTRA; |
| 4758 | |
| 4759 | cx = tx; |
| 4760 | cy = ty; |
| 4761 | cw = tw = TILE_SIZE-1-2*GRIDEXTRA; |
| 4762 | ch = th = TILE_SIZE-1-2*GRIDEXTRA; |
| 4763 | |
| 4764 | if (x > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x-1]) |
| 4765 | cx -= GRIDEXTRA, cw += GRIDEXTRA; |
| 4766 | if (x+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x+1]) |
| 4767 | cw += GRIDEXTRA; |
| 4768 | if (y > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y-1)*cr+x]) |
| 4769 | cy -= GRIDEXTRA, ch += GRIDEXTRA; |
| 4770 | if (y+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y+1)*cr+x]) |
| 4771 | ch += GRIDEXTRA; |
| 4772 | |
| 4773 | clip(dr, cx, cy, cw, ch); |
| 4774 | |
| 4775 | /* background needs erasing */ |
| 4776 | draw_rect(dr, cx, cy, cw, ch, |
| 4777 | ((hl & 15) == 1 ? COL_HIGHLIGHT : |
| 4778 | (ds->xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x))) ? COL_XDIAGONALS : |
| 4779 | COL_BACKGROUND)); |
| 4780 | |
| 4781 | /* |
| 4782 | * Draw the corners of thick lines in corner-adjacent squares, |
| 4783 | * which jut into this square by one pixel. |
| 4784 | */ |
| 4785 | if (x > 0 && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x-1]) |
| 4786 | draw_rect(dr, tx-GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
| 4787 | if (x+1 < cr && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x+1]) |
| 4788 | draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
| 4789 | if (x > 0 && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x-1]) |
| 4790 | draw_rect(dr, tx-GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
| 4791 | if (x+1 < cr && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x+1]) |
| 4792 | draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
| 4793 | |
| 4794 | /* pencil-mode highlight */ |
| 4795 | if ((hl & 15) == 2) { |
| 4796 | int coords[6]; |
| 4797 | coords[0] = cx; |
| 4798 | coords[1] = cy; |
| 4799 | coords[2] = cx+cw/2; |
| 4800 | coords[3] = cy; |
| 4801 | coords[4] = cx; |
| 4802 | coords[5] = cy+ch/2; |
| 4803 | draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT); |
| 4804 | } |
| 4805 | |
| 4806 | if (state->kblocks) { |
| 4807 | int t = GRIDEXTRA * 3; |
| 4808 | int kcx, kcy, kcw, kch; |
| 4809 | int kl, kt, kr, kb; |
| 4810 | int has_left = 0, has_right = 0, has_top = 0, has_bottom = 0; |
| 4811 | |
| 4812 | /* |
| 4813 | * In non-jigsaw mode, the Killer cages are placed at a |
| 4814 | * fixed offset from the outer edge of the cell dividing |
| 4815 | * lines, so that they look right whether those lines are |
| 4816 | * thick or thin. In jigsaw mode, however, doing this will |
| 4817 | * sometimes cause the cage outlines in adjacent squares to |
| 4818 | * fail to match up with each other, so we must offset a |
| 4819 | * fixed amount from the _centre_ of the cell dividing |
| 4820 | * lines. |
| 4821 | */ |
| 4822 | if (state->blocks->r == 1) { |
| 4823 | kcx = tx; |
| 4824 | kcy = ty; |
| 4825 | kcw = tw; |
| 4826 | kch = th; |
| 4827 | } else { |
| 4828 | kcx = cx; |
| 4829 | kcy = cy; |
| 4830 | kcw = cw; |
| 4831 | kch = ch; |
| 4832 | } |
| 4833 | kl = kcx - 1; |
| 4834 | kt = kcy - 1; |
| 4835 | kr = kcx + kcw; |
| 4836 | kb = kcy + kch; |
| 4837 | |
| 4838 | /* |
| 4839 | * First, draw the lines dividing this area from neighbouring |
| 4840 | * different areas. |
| 4841 | */ |
| 4842 | if (x == 0 || state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[y*cr+x-1]) |
| 4843 | has_left = 1, kl += t; |
| 4844 | if (x+1 >= cr || state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[y*cr+x+1]) |
| 4845 | has_right = 1, kr -= t; |
| 4846 | if (y == 0 || state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y-1)*cr+x]) |
| 4847 | has_top = 1, kt += t; |
| 4848 | if (y+1 >= cr || state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y+1)*cr+x]) |
| 4849 | has_bottom = 1, kb -= t; |
| 4850 | if (has_top) |
| 4851 | draw_line(dr, kl, kt, kr, kt, col_killer); |
| 4852 | if (has_bottom) |
| 4853 | draw_line(dr, kl, kb, kr, kb, col_killer); |
| 4854 | if (has_left) |
| 4855 | draw_line(dr, kl, kt, kl, kb, col_killer); |
| 4856 | if (has_right) |
| 4857 | draw_line(dr, kr, kt, kr, kb, col_killer); |
| 4858 | /* |
| 4859 | * Now, take care of the corners (just as for the normal borders). |
| 4860 | * We only need a corner if there wasn't a full edge. |
| 4861 | */ |
| 4862 | if (x > 0 && y > 0 && !has_left && !has_top |
| 4863 | && state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y-1)*cr+x-1]) |
| 4864 | { |
| 4865 | draw_line(dr, kl, kt + t, kl + t, kt + t, col_killer); |
| 4866 | draw_line(dr, kl + t, kt, kl + t, kt + t, col_killer); |
| 4867 | } |
| 4868 | if (x+1 < cr && y > 0 && !has_right && !has_top |
| 4869 | && state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y-1)*cr+x+1]) |
| 4870 | { |
| 4871 | draw_line(dr, kcx + kcw - t, kt + t, kcx + kcw, kt + t, col_killer); |
| 4872 | draw_line(dr, kcx + kcw - t, kt, kcx + kcw - t, kt + t, col_killer); |
| 4873 | } |
| 4874 | if (x > 0 && y+1 < cr && !has_left && !has_bottom |
| 4875 | && state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y+1)*cr+x-1]) |
| 4876 | { |
| 4877 | draw_line(dr, kl, kcy + kch - t, kl + t, kcy + kch - t, col_killer); |
| 4878 | draw_line(dr, kl + t, kcy + kch - t, kl + t, kcy + kch, col_killer); |
| 4879 | } |
| 4880 | if (x+1 < cr && y+1 < cr && !has_right && !has_bottom |
| 4881 | && state->kblocks->whichblock[y*cr+x] != state->kblocks->whichblock[(y+1)*cr+x+1]) |
| 4882 | { |
| 4883 | draw_line(dr, kcx + kcw - t, kcy + kch - t, kcx + kcw - t, kcy + kch, col_killer); |
| 4884 | draw_line(dr, kcx + kcw - t, kcy + kch - t, kcx + kcw, kcy + kch - t, col_killer); |
| 4885 | } |
| 4886 | |
| 4887 | } |
| 4888 | |
| 4889 | if (state->killer && state->kgrid[y*cr+x]) { |
| 4890 | sprintf (str, "%d", state->kgrid[y*cr+x]); |
| 4891 | draw_text(dr, tx + GRIDEXTRA * 4, ty + GRIDEXTRA * 4 + TILE_SIZE/4, |
| 4892 | FONT_VARIABLE, TILE_SIZE/4, ALIGN_VNORMAL | ALIGN_HLEFT, |
| 4893 | col_killer, str); |
| 4894 | } |
| 4895 | |
| 4896 | /* new number needs drawing? */ |
| 4897 | if (state->grid[y*cr+x]) { |
| 4898 | str[1] = '\0'; |
| 4899 | str[0] = state->grid[y*cr+x] + '0'; |
| 4900 | if (str[0] > '9') |
| 4901 | str[0] += 'a' - ('9'+1); |
| 4902 | draw_text(dr, tx + TILE_SIZE/2, ty + TILE_SIZE/2, |
| 4903 | FONT_VARIABLE, TILE_SIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE, |
| 4904 | state->immutable[y*cr+x] ? COL_CLUE : (hl & 16) ? COL_ERROR : COL_USER, str); |
| 4905 | } else { |
| 4906 | int i, j, npencil; |
| 4907 | int pl, pr, pt, pb; |
| 4908 | float bestsize; |
| 4909 | int pw, ph, minph, pbest, fontsize; |
| 4910 | |
| 4911 | /* Count the pencil marks required. */ |
| 4912 | for (i = npencil = 0; i < cr; i++) |
| 4913 | if (state->pencil[(y*cr+x)*cr+i]) |
| 4914 | npencil++; |
| 4915 | if (npencil) { |
| 4916 | |
| 4917 | minph = 2; |
| 4918 | |
| 4919 | /* |
| 4920 | * Determine the bounding rectangle within which we're going |
| 4921 | * to put the pencil marks. |
| 4922 | */ |
| 4923 | /* Start with the whole square */ |
| 4924 | pl = tx + GRIDEXTRA; |
| 4925 | pr = pl + TILE_SIZE - GRIDEXTRA; |
| 4926 | pt = ty + GRIDEXTRA; |
| 4927 | pb = pt + TILE_SIZE - GRIDEXTRA; |
| 4928 | if (state->killer) { |
| 4929 | /* |
| 4930 | * Make space for the Killer cages. We do this |
| 4931 | * unconditionally, for uniformity between squares, |
| 4932 | * rather than making it depend on whether a Killer |
| 4933 | * cage edge is actually present on any given side. |
| 4934 | */ |
| 4935 | pl += GRIDEXTRA * 3; |
| 4936 | pr -= GRIDEXTRA * 3; |
| 4937 | pt += GRIDEXTRA * 3; |
| 4938 | pb -= GRIDEXTRA * 3; |
| 4939 | if (state->kgrid[y*cr+x] != 0) { |
| 4940 | /* Make further space for the Killer number. */ |
| 4941 | pt += TILE_SIZE/4; |
| 4942 | /* minph--; */ |
| 4943 | } |
| 4944 | } |
| 4945 | |
| 4946 | /* |
| 4947 | * We arrange our pencil marks in a grid layout, with |
| 4948 | * the number of rows and columns adjusted to allow the |
| 4949 | * maximum font size. |
| 4950 | * |
| 4951 | * So now we work out what the grid size ought to be. |
| 4952 | */ |
| 4953 | bestsize = 0.0; |
| 4954 | pbest = 0; |
| 4955 | /* Minimum */ |
| 4956 | for (pw = 3; pw < max(npencil,4); pw++) { |
| 4957 | float fw, fh, fs; |
| 4958 | |
| 4959 | ph = (npencil + pw - 1) / pw; |
| 4960 | ph = max(ph, minph); |
| 4961 | fw = (pr - pl) / (float)pw; |
| 4962 | fh = (pb - pt) / (float)ph; |
| 4963 | fs = min(fw, fh); |
| 4964 | if (fs > bestsize) { |
| 4965 | bestsize = fs; |
| 4966 | pbest = pw; |
| 4967 | } |
| 4968 | } |
| 4969 | assert(pbest > 0); |
| 4970 | pw = pbest; |
| 4971 | ph = (npencil + pw - 1) / pw; |
| 4972 | ph = max(ph, minph); |
| 4973 | |
| 4974 | /* |
| 4975 | * Now we've got our grid dimensions, work out the pixel |
| 4976 | * size of a grid element, and round it to the nearest |
| 4977 | * pixel. (We don't want rounding errors to make the |
| 4978 | * grid look uneven at low pixel sizes.) |
| 4979 | */ |
| 4980 | fontsize = min((pr - pl) / pw, (pb - pt) / ph); |
| 4981 | |
| 4982 | /* |
| 4983 | * Centre the resulting figure in the square. |
| 4984 | */ |
| 4985 | pl = tx + (TILE_SIZE - fontsize * pw) / 2; |
| 4986 | pt = ty + (TILE_SIZE - fontsize * ph) / 2; |
| 4987 | |
| 4988 | /* |
| 4989 | * And move it down a bit if it's collided with the |
| 4990 | * Killer cage number. |
| 4991 | */ |
| 4992 | if (state->killer && state->kgrid[y*cr+x] != 0) { |
| 4993 | pt = max(pt, ty + GRIDEXTRA * 3 + TILE_SIZE/4); |
| 4994 | } |
| 4995 | |
| 4996 | /* |
| 4997 | * Now actually draw the pencil marks. |
| 4998 | */ |
| 4999 | for (i = j = 0; i < cr; i++) |
| 5000 | if (state->pencil[(y*cr+x)*cr+i]) { |
| 5001 | int dx = j % pw, dy = j / pw; |
| 5002 | |
| 5003 | str[1] = '\0'; |
| 5004 | str[0] = i + '1'; |
| 5005 | if (str[0] > '9') |
| 5006 | str[0] += 'a' - ('9'+1); |
| 5007 | draw_text(dr, pl + fontsize * (2*dx+1) / 2, |
| 5008 | pt + fontsize * (2*dy+1) / 2, |
| 5009 | FONT_VARIABLE, fontsize, |
| 5010 | ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str); |
| 5011 | j++; |
| 5012 | } |
| 5013 | } |
| 5014 | } |
| 5015 | |
| 5016 | unclip(dr); |
| 5017 | |
| 5018 | draw_update(dr, cx, cy, cw, ch); |
| 5019 | |
| 5020 | ds->grid[y*cr+x] = state->grid[y*cr+x]; |
| 5021 | memcpy(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr); |
| 5022 | ds->hl[y*cr+x] = hl; |
| 5023 | } |
| 5024 | |
| 5025 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
| 5026 | game_state *state, int dir, game_ui *ui, |
| 5027 | float animtime, float flashtime) |
| 5028 | { |
| 5029 | int cr = state->cr; |
| 5030 | int x, y; |
| 5031 | |
| 5032 | if (!ds->started) { |
| 5033 | /* |
| 5034 | * The initial contents of the window are not guaranteed |
| 5035 | * and can vary with front ends. To be on the safe side, |
| 5036 | * all games should start by drawing a big |
| 5037 | * background-colour rectangle covering the whole window. |
| 5038 | */ |
| 5039 | draw_rect(dr, 0, 0, SIZE(cr), SIZE(cr), COL_BACKGROUND); |
| 5040 | |
| 5041 | /* |
| 5042 | * Draw the grid. We draw it as a big thick rectangle of |
| 5043 | * COL_GRID initially; individual calls to draw_number() |
| 5044 | * will poke the right-shaped holes in it. |
| 5045 | */ |
| 5046 | draw_rect(dr, BORDER-GRIDEXTRA, BORDER-GRIDEXTRA, |
| 5047 | cr*TILE_SIZE+1+2*GRIDEXTRA, cr*TILE_SIZE+1+2*GRIDEXTRA, |
| 5048 | COL_GRID); |
| 5049 | } |
| 5050 | |
| 5051 | /* |
| 5052 | * This array is used to keep track of rows, columns and boxes |
| 5053 | * which contain a number more than once. |
| 5054 | */ |
| 5055 | for (x = 0; x < cr * ds->nregions; x++) |
| 5056 | ds->entered_items[x] = 0; |
| 5057 | for (x = 0; x < cr; x++) |
| 5058 | for (y = 0; y < cr; y++) { |
| 5059 | digit d = state->grid[y*cr+x]; |
| 5060 | if (d) { |
| 5061 | int box, kbox; |
| 5062 | |
| 5063 | /* Rows */ |
| 5064 | ds->entered_items[x*cr+d-1]++; |
| 5065 | |
| 5066 | /* Columns */ |
| 5067 | ds->entered_items[(y+cr)*cr+d-1]++; |
| 5068 | |
| 5069 | /* Blocks */ |
| 5070 | box = state->blocks->whichblock[y*cr+x]; |
| 5071 | ds->entered_items[(box+2*cr)*cr+d-1]++; |
| 5072 | |
| 5073 | /* Diagonals */ |
| 5074 | if (ds->xtype) { |
| 5075 | if (ondiag0(y*cr+x)) |
| 5076 | ds->entered_items[(3*cr)*cr+d-1]++; |
| 5077 | if (ondiag1(y*cr+x)) |
| 5078 | ds->entered_items[(3*cr+1)*cr+d-1]++; |
| 5079 | } |
| 5080 | |
| 5081 | /* Killer cages */ |
| 5082 | if (state->kblocks) { |
| 5083 | kbox = state->kblocks->whichblock[y*cr+x]; |
| 5084 | ds->entered_items[(kbox+3*cr+2)*cr+d-1]++; |
| 5085 | } |
| 5086 | } |
| 5087 | } |
| 5088 | |
| 5089 | /* |
| 5090 | * Draw any numbers which need redrawing. |
| 5091 | */ |
| 5092 | for (x = 0; x < cr; x++) { |
| 5093 | for (y = 0; y < cr; y++) { |
| 5094 | int highlight = 0; |
| 5095 | digit d = state->grid[y*cr+x]; |
| 5096 | |
| 5097 | if (flashtime > 0 && |
| 5098 | (flashtime <= FLASH_TIME/3 || |
| 5099 | flashtime >= FLASH_TIME*2/3)) |
| 5100 | highlight = 1; |
| 5101 | |
| 5102 | /* Highlight active input areas. */ |
| 5103 | if (x == ui->hx && y == ui->hy && ui->hshow) |
| 5104 | highlight = ui->hpencil ? 2 : 1; |
| 5105 | |
| 5106 | /* Mark obvious errors (ie, numbers which occur more than once |
| 5107 | * in a single row, column, or box). */ |
| 5108 | if (d && (ds->entered_items[x*cr+d-1] > 1 || |
| 5109 | ds->entered_items[(y+cr)*cr+d-1] > 1 || |
| 5110 | ds->entered_items[(state->blocks->whichblock[y*cr+x] |
| 5111 | +2*cr)*cr+d-1] > 1 || |
| 5112 | (ds->xtype && ((ondiag0(y*cr+x) && |
| 5113 | ds->entered_items[(3*cr)*cr+d-1] > 1) || |
| 5114 | (ondiag1(y*cr+x) && |
| 5115 | ds->entered_items[(3*cr+1)*cr+d-1]>1)))|| |
| 5116 | (state->kblocks && |
| 5117 | ds->entered_items[(state->kblocks->whichblock[y*cr+x] |
| 5118 | +3*cr+2)*cr+d-1] > 1))) |
| 5119 | highlight |= 16; |
| 5120 | |
| 5121 | if (d && state->kblocks) { |
| 5122 | int i, b = state->kblocks->whichblock[y*cr+x]; |
| 5123 | int n_squares = state->kblocks->nr_squares[b]; |
| 5124 | int sum = 0, clue = 0; |
| 5125 | for (i = 0; i < n_squares; i++) { |
| 5126 | int xy = state->kblocks->blocks[b][i]; |
| 5127 | if (state->grid[xy] == 0) |
| 5128 | break; |
| 5129 | |
| 5130 | sum += state->grid[xy]; |
| 5131 | if (state->kgrid[xy]) { |
| 5132 | assert(clue == 0); |
| 5133 | clue = state->kgrid[xy]; |
| 5134 | } |
| 5135 | } |
| 5136 | |
| 5137 | if (i == n_squares) { |
| 5138 | assert(clue != 0); |
| 5139 | if (sum != clue) |
| 5140 | highlight |= 32; |
| 5141 | } |
| 5142 | } |
| 5143 | |
| 5144 | draw_number(dr, ds, state, x, y, highlight); |
| 5145 | } |
| 5146 | } |
| 5147 | |
| 5148 | /* |
| 5149 | * Update the _entire_ grid if necessary. |
| 5150 | */ |
| 5151 | if (!ds->started) { |
| 5152 | draw_update(dr, 0, 0, SIZE(cr), SIZE(cr)); |
| 5153 | ds->started = TRUE; |
| 5154 | } |
| 5155 | } |
| 5156 | |
| 5157 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
| 5158 | int dir, game_ui *ui) |
| 5159 | { |
| 5160 | return 0.0F; |
| 5161 | } |
| 5162 | |
| 5163 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
| 5164 | int dir, game_ui *ui) |
| 5165 | { |
| 5166 | if (!oldstate->completed && newstate->completed && |
| 5167 | !oldstate->cheated && !newstate->cheated) |
| 5168 | return FLASH_TIME; |
| 5169 | return 0.0F; |
| 5170 | } |
| 5171 | |
| 5172 | static int game_timing_state(game_state *state, game_ui *ui) |
| 5173 | { |
| 5174 | if (state->completed) |
| 5175 | return FALSE; |
| 5176 | return TRUE; |
| 5177 | } |
| 5178 | |
| 5179 | static void game_print_size(game_params *params, float *x, float *y) |
| 5180 | { |
| 5181 | int pw, ph; |
| 5182 | |
| 5183 | /* |
| 5184 | * I'll use 9mm squares by default. They should be quite big |
| 5185 | * for this game, because players will want to jot down no end |
| 5186 | * of pencil marks in the squares. |
| 5187 | */ |
| 5188 | game_compute_size(params, 900, &pw, &ph); |
| 5189 | *x = pw / 100.0F; |
| 5190 | *y = ph / 100.0F; |
| 5191 | } |
| 5192 | |
| 5193 | /* |
| 5194 | * Subfunction to draw the thick lines between cells. In order to do |
| 5195 | * this using the line-drawing rather than rectangle-drawing API (so |
| 5196 | * as to get line thicknesses to scale correctly) and yet have |
| 5197 | * correctly mitred joins between lines, we must do this by tracing |
| 5198 | * the boundary of each sub-block and drawing it in one go as a |
| 5199 | * single polygon. |
| 5200 | * |
| 5201 | * This subfunction is also reused with thinner dotted lines to |
| 5202 | * outline the Killer cages, this time offsetting the outline toward |
| 5203 | * the interior of the affected squares. |
| 5204 | */ |
| 5205 | static void outline_block_structure(drawing *dr, game_drawstate *ds, |
| 5206 | game_state *state, |
| 5207 | struct block_structure *blocks, |
| 5208 | int ink, int inset) |
| 5209 | { |
| 5210 | int cr = state->cr; |
| 5211 | int *coords; |
| 5212 | int bi, i, n; |
| 5213 | int x, y, dx, dy, sx, sy, sdx, sdy; |
| 5214 | |
| 5215 | /* |
| 5216 | * Maximum perimeter of a k-omino is 2k+2. (Proof: start |
| 5217 | * with k unconnected squares, with total perimeter 4k. |
| 5218 | * Now repeatedly join two disconnected components |
| 5219 | * together into a larger one; every time you do so you |
| 5220 | * remove at least two unit edges, and you require k-1 of |
| 5221 | * these operations to create a single connected piece, so |
| 5222 | * you must have at most 4k-2(k-1) = 2k+2 unit edges left |
| 5223 | * afterwards.) |
| 5224 | */ |
| 5225 | coords = snewn(4*cr+4, int); /* 2k+2 points, 2 coords per point */ |
| 5226 | |
| 5227 | /* |
| 5228 | * Iterate over all the blocks. |
| 5229 | */ |
| 5230 | for (bi = 0; bi < blocks->nr_blocks; bi++) { |
| 5231 | if (blocks->nr_squares[bi] == 0) |
| 5232 | continue; |
| 5233 | |
| 5234 | /* |
| 5235 | * For each block, find a starting square within it |
| 5236 | * which has a boundary at the left. |
| 5237 | */ |
| 5238 | for (i = 0; i < cr; i++) { |
| 5239 | int j = blocks->blocks[bi][i]; |
| 5240 | if (j % cr == 0 || blocks->whichblock[j-1] != bi) |
| 5241 | break; |
| 5242 | } |
| 5243 | assert(i < cr); /* every block must have _some_ leftmost square */ |
| 5244 | x = blocks->blocks[bi][i] % cr; |
| 5245 | y = blocks->blocks[bi][i] / cr; |
| 5246 | dx = -1; |
| 5247 | dy = 0; |
| 5248 | |
| 5249 | /* |
| 5250 | * Now begin tracing round the perimeter. At all |
| 5251 | * times, (x,y) describes some square within the |
| 5252 | * block, and (x+dx,y+dy) is some adjacent square |
| 5253 | * outside it; so the edge between those two squares |
| 5254 | * is always an edge of the block. |
| 5255 | */ |
| 5256 | sx = x, sy = y, sdx = dx, sdy = dy; /* save starting position */ |
| 5257 | n = 0; |
| 5258 | do { |
| 5259 | int cx, cy, tx, ty, nin; |
| 5260 | |
| 5261 | /* |
| 5262 | * Advance to the next edge, by looking at the two |
| 5263 | * squares beyond it. If they're both outside the block, |
| 5264 | * we turn right (by leaving x,y the same and rotating |
| 5265 | * dx,dy clockwise); if they're both inside, we turn |
| 5266 | * left (by rotating dx,dy anticlockwise and contriving |
| 5267 | * to leave x+dx,y+dy unchanged); if one of each, we go |
| 5268 | * straight on (and may enforce by assertion that |
| 5269 | * they're one of each the _right_ way round). |
| 5270 | */ |
| 5271 | nin = 0; |
| 5272 | tx = x - dy + dx; |
| 5273 | ty = y + dx + dy; |
| 5274 | nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr && |
| 5275 | blocks->whichblock[ty*cr+tx] == bi); |
| 5276 | tx = x - dy; |
| 5277 | ty = y + dx; |
| 5278 | nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr && |
| 5279 | blocks->whichblock[ty*cr+tx] == bi); |
| 5280 | if (nin == 0) { |
| 5281 | /* |
| 5282 | * Turn right. |
| 5283 | */ |
| 5284 | int tmp; |
| 5285 | tmp = dx; |
| 5286 | dx = -dy; |
| 5287 | dy = tmp; |
| 5288 | } else if (nin == 2) { |
| 5289 | /* |
| 5290 | * Turn left. |
| 5291 | */ |
| 5292 | int tmp; |
| 5293 | |
| 5294 | x += dx; |
| 5295 | y += dy; |
| 5296 | |
| 5297 | tmp = dx; |
| 5298 | dx = dy; |
| 5299 | dy = -tmp; |
| 5300 | |
| 5301 | x -= dx; |
| 5302 | y -= dy; |
| 5303 | } else { |
| 5304 | /* |
| 5305 | * Go straight on. |
| 5306 | */ |
| 5307 | x -= dy; |
| 5308 | y += dx; |
| 5309 | } |
| 5310 | |
| 5311 | /* |
| 5312 | * Now enforce by assertion that we ended up |
| 5313 | * somewhere sensible. |
| 5314 | */ |
| 5315 | assert(x >= 0 && x < cr && y >= 0 && y < cr && |
| 5316 | blocks->whichblock[y*cr+x] == bi); |
| 5317 | assert(x+dx < 0 || x+dx >= cr || y+dy < 0 || y+dy >= cr || |
| 5318 | blocks->whichblock[(y+dy)*cr+(x+dx)] != bi); |
| 5319 | |
| 5320 | /* |
| 5321 | * Record the point we just went past at one end of the |
| 5322 | * edge. To do this, we translate (x,y) down and right |
| 5323 | * by half a unit (so they're describing a point in the |
| 5324 | * _centre_ of the square) and then translate back again |
| 5325 | * in a manner rotated by dy and dx. |
| 5326 | */ |
| 5327 | assert(n < 2*cr+2); |
| 5328 | cx = ((2*x+1) + dy + dx) / 2; |
| 5329 | cy = ((2*y+1) - dx + dy) / 2; |
| 5330 | coords[2*n+0] = BORDER + cx * TILE_SIZE; |
| 5331 | coords[2*n+1] = BORDER + cy * TILE_SIZE; |
| 5332 | coords[2*n+0] -= dx * inset; |
| 5333 | coords[2*n+1] -= dy * inset; |
| 5334 | if (nin == 0) { |
| 5335 | /* |
| 5336 | * We turned right, so inset this corner back along |
| 5337 | * the edge towards the centre of the square. |
| 5338 | */ |
| 5339 | coords[2*n+0] -= dy * inset; |
| 5340 | coords[2*n+1] += dx * inset; |
| 5341 | } else if (nin == 2) { |
| 5342 | /* |
| 5343 | * We turned left, so inset this corner further |
| 5344 | * _out_ along the edge into the next square. |
| 5345 | */ |
| 5346 | coords[2*n+0] += dy * inset; |
| 5347 | coords[2*n+1] -= dx * inset; |
| 5348 | } |
| 5349 | n++; |
| 5350 | |
| 5351 | } while (x != sx || y != sy || dx != sdx || dy != sdy); |
| 5352 | |
| 5353 | /* |
| 5354 | * That's our polygon; now draw it. |
| 5355 | */ |
| 5356 | draw_polygon(dr, coords, n, -1, ink); |
| 5357 | } |
| 5358 | |
| 5359 | sfree(coords); |
| 5360 | } |
| 5361 | |
| 5362 | static void game_print(drawing *dr, game_state *state, int tilesize) |
| 5363 | { |
| 5364 | int cr = state->cr; |
| 5365 | int ink = print_mono_colour(dr, 0); |
| 5366 | int x, y; |
| 5367 | |
| 5368 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
| 5369 | game_drawstate ads, *ds = &ads; |
| 5370 | game_set_size(dr, ds, NULL, tilesize); |
| 5371 | |
| 5372 | /* |
| 5373 | * Border. |
| 5374 | */ |
| 5375 | print_line_width(dr, 3 * TILE_SIZE / 40); |
| 5376 | draw_rect_outline(dr, BORDER, BORDER, cr*TILE_SIZE, cr*TILE_SIZE, ink); |
| 5377 | |
| 5378 | /* |
| 5379 | * Highlight X-diagonal squares. |
| 5380 | */ |
| 5381 | if (state->xtype) { |
| 5382 | int i; |
| 5383 | int xhighlight = print_grey_colour(dr, 0.90F); |
| 5384 | |
| 5385 | for (i = 0; i < cr; i++) |
| 5386 | draw_rect(dr, BORDER + i*TILE_SIZE, BORDER + i*TILE_SIZE, |
| 5387 | TILE_SIZE, TILE_SIZE, xhighlight); |
| 5388 | for (i = 0; i < cr; i++) |
| 5389 | if (i*2 != cr-1) /* avoid redoing centre square, just for fun */ |
| 5390 | draw_rect(dr, BORDER + i*TILE_SIZE, |
| 5391 | BORDER + (cr-1-i)*TILE_SIZE, |
| 5392 | TILE_SIZE, TILE_SIZE, xhighlight); |
| 5393 | } |
| 5394 | |
| 5395 | /* |
| 5396 | * Main grid. |
| 5397 | */ |
| 5398 | for (x = 1; x < cr; x++) { |
| 5399 | print_line_width(dr, TILE_SIZE / 40); |
| 5400 | draw_line(dr, BORDER+x*TILE_SIZE, BORDER, |
| 5401 | BORDER+x*TILE_SIZE, BORDER+cr*TILE_SIZE, ink); |
| 5402 | } |
| 5403 | for (y = 1; y < cr; y++) { |
| 5404 | print_line_width(dr, TILE_SIZE / 40); |
| 5405 | draw_line(dr, BORDER, BORDER+y*TILE_SIZE, |
| 5406 | BORDER+cr*TILE_SIZE, BORDER+y*TILE_SIZE, ink); |
| 5407 | } |
| 5408 | |
| 5409 | /* |
| 5410 | * Thick lines between cells. |
| 5411 | */ |
| 5412 | print_line_width(dr, 3 * TILE_SIZE / 40); |
| 5413 | outline_block_structure(dr, ds, state, state->blocks, ink, 0); |
| 5414 | |
| 5415 | /* |
| 5416 | * Killer cages and their totals. |
| 5417 | */ |
| 5418 | if (state->kblocks) { |
| 5419 | print_line_width(dr, TILE_SIZE / 40); |
| 5420 | print_line_dotted(dr, TRUE); |
| 5421 | outline_block_structure(dr, ds, state, state->kblocks, ink, |
| 5422 | 5 * TILE_SIZE / 40); |
| 5423 | print_line_dotted(dr, FALSE); |
| 5424 | for (y = 0; y < cr; y++) |
| 5425 | for (x = 0; x < cr; x++) |
| 5426 | if (state->kgrid[y*cr+x]) { |
| 5427 | char str[20]; |
| 5428 | sprintf(str, "%d", state->kgrid[y*cr+x]); |
| 5429 | draw_text(dr, |
| 5430 | BORDER+x*TILE_SIZE + 7*TILE_SIZE/40, |
| 5431 | BORDER+y*TILE_SIZE + 16*TILE_SIZE/40, |
| 5432 | FONT_VARIABLE, TILE_SIZE/4, |
| 5433 | ALIGN_VNORMAL | ALIGN_HLEFT, |
| 5434 | ink, str); |
| 5435 | } |
| 5436 | } |
| 5437 | |
| 5438 | /* |
| 5439 | * Standard (non-Killer) clue numbers. |
| 5440 | */ |
| 5441 | for (y = 0; y < cr; y++) |
| 5442 | for (x = 0; x < cr; x++) |
| 5443 | if (state->grid[y*cr+x]) { |
| 5444 | char str[2]; |
| 5445 | str[1] = '\0'; |
| 5446 | str[0] = state->grid[y*cr+x] + '0'; |
| 5447 | if (str[0] > '9') |
| 5448 | str[0] += 'a' - ('9'+1); |
| 5449 | draw_text(dr, BORDER + x*TILE_SIZE + TILE_SIZE/2, |
| 5450 | BORDER + y*TILE_SIZE + TILE_SIZE/2, |
| 5451 | FONT_VARIABLE, TILE_SIZE/2, |
| 5452 | ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str); |
| 5453 | } |
| 5454 | } |
| 5455 | |
| 5456 | #ifdef COMBINED |
| 5457 | #define thegame solo |
| 5458 | #endif |
| 5459 | |
| 5460 | const struct game thegame = { |
| 5461 | "Solo", "games.solo", "solo", |
| 5462 | default_params, |
| 5463 | game_fetch_preset, |
| 5464 | decode_params, |
| 5465 | encode_params, |
| 5466 | free_params, |
| 5467 | dup_params, |
| 5468 | TRUE, game_configure, custom_params, |
| 5469 | validate_params, |
| 5470 | new_game_desc, |
| 5471 | validate_desc, |
| 5472 | new_game, |
| 5473 | dup_game, |
| 5474 | free_game, |
| 5475 | TRUE, solve_game, |
| 5476 | TRUE, game_can_format_as_text_now, game_text_format, |
| 5477 | new_ui, |
| 5478 | free_ui, |
| 5479 | encode_ui, |
| 5480 | decode_ui, |
| 5481 | game_changed_state, |
| 5482 | interpret_move, |
| 5483 | execute_move, |
| 5484 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
| 5485 | game_colours, |
| 5486 | game_new_drawstate, |
| 5487 | game_free_drawstate, |
| 5488 | game_redraw, |
| 5489 | game_anim_length, |
| 5490 | game_flash_length, |
| 5491 | TRUE, FALSE, game_print_size, game_print, |
| 5492 | FALSE, /* wants_statusbar */ |
| 5493 | FALSE, game_timing_state, |
| 5494 | REQUIRE_RBUTTON | REQUIRE_NUMPAD, /* flags */ |
| 5495 | }; |
| 5496 | |
| 5497 | #ifdef STANDALONE_SOLVER |
| 5498 | |
| 5499 | int main(int argc, char **argv) |
| 5500 | { |
| 5501 | game_params *p; |
| 5502 | game_state *s; |
| 5503 | char *id = NULL, *desc, *err; |
| 5504 | int grade = FALSE; |
| 5505 | struct difficulty dlev; |
| 5506 | |
| 5507 | while (--argc > 0) { |
| 5508 | char *p = *++argv; |
| 5509 | if (!strcmp(p, "-v")) { |
| 5510 | solver_show_working = TRUE; |
| 5511 | } else if (!strcmp(p, "-g")) { |
| 5512 | grade = TRUE; |
| 5513 | } else if (*p == '-') { |
| 5514 | fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p); |
| 5515 | return 1; |
| 5516 | } else { |
| 5517 | id = p; |
| 5518 | } |
| 5519 | } |
| 5520 | |
| 5521 | if (!id) { |
| 5522 | fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]); |
| 5523 | return 1; |
| 5524 | } |
| 5525 | |
| 5526 | desc = strchr(id, ':'); |
| 5527 | if (!desc) { |
| 5528 | fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); |
| 5529 | return 1; |
| 5530 | } |
| 5531 | *desc++ = '\0'; |
| 5532 | |
| 5533 | p = default_params(); |
| 5534 | decode_params(p, id); |
| 5535 | err = validate_desc(p, desc); |
| 5536 | if (err) { |
| 5537 | fprintf(stderr, "%s: %s\n", argv[0], err); |
| 5538 | return 1; |
| 5539 | } |
| 5540 | s = new_game(NULL, p, desc); |
| 5541 | |
| 5542 | dlev.maxdiff = DIFF_RECURSIVE; |
| 5543 | dlev.maxkdiff = DIFF_KINTERSECT; |
| 5544 | solver(s->cr, s->blocks, s->kblocks, s->xtype, s->grid, s->kgrid, &dlev); |
| 5545 | if (grade) { |
| 5546 | printf("Difficulty rating: %s\n", |
| 5547 | dlev.diff==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)": |
| 5548 | dlev.diff==DIFF_SIMPLE ? "Basic (row/column/number elimination required)": |
| 5549 | dlev.diff==DIFF_INTERSECT ? "Intermediate (intersectional analysis required)": |
| 5550 | dlev.diff==DIFF_SET ? "Advanced (set elimination required)": |
| 5551 | dlev.diff==DIFF_EXTREME ? "Extreme (complex non-recursive techniques required)": |
| 5552 | dlev.diff==DIFF_RECURSIVE ? "Unreasonable (guesswork and backtracking required)": |
| 5553 | dlev.diff==DIFF_AMBIGUOUS ? "Ambiguous (multiple solutions exist)": |
| 5554 | dlev.diff==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)": |
| 5555 | "INTERNAL ERROR: unrecognised difficulty code"); |
| 5556 | if (p->killer) |
| 5557 | printf("Killer diffculty: %s\n", |
| 5558 | dlev.kdiff==DIFF_KSINGLE ? "Trivial (single square cages only)": |
| 5559 | dlev.kdiff==DIFF_KMINMAX ? "Simple (maximum sum analysis required)": |
| 5560 | dlev.kdiff==DIFF_KSUMS ? "Intermediate (sum possibilities)": |
| 5561 | dlev.kdiff==DIFF_KINTERSECT ? "Advanced (sum region intersections)": |
| 5562 | "INTERNAL ERROR: unrecognised difficulty code"); |
| 5563 | } else { |
| 5564 | printf("%s\n", grid_text_format(s->cr, s->blocks, s->xtype, s->grid)); |
| 5565 | } |
| 5566 | |
| 5567 | return 0; |
| 5568 | } |
| 5569 | |
| 5570 | #endif |
| 5571 | |
| 5572 | /* vim: set shiftwidth=4 tabstop=8: */ |