1d8e8ad8 |
1 | /* |
2 | * solo.c: the number-placing puzzle most popularly known as `Sudoku'. |
3 | * |
4 | * TODO: |
5 | * |
c8266e03 |
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 | * |
ef57b17d |
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. |
1d8e8ad8 |
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. |
c8266e03 |
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. |
1d8e8ad8 |
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 | |
7c568a48 |
92 | #ifdef STANDALONE_SOLVER |
93 | #include <stdarg.h> |
94 | int solver_show_working; |
95 | #endif |
96 | |
1d8e8ad8 |
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 | |
1e3e152d |
110 | #define PREFERRED_TILE_SIZE 32 |
111 | #define TILE_SIZE (ds->tilesize) |
112 | #define BORDER (TILE_SIZE / 2) |
1d8e8ad8 |
113 | |
114 | #define FLASH_TIME 0.4F |
115 | |
154bf9b1 |
116 | enum { SYMM_NONE, SYMM_ROT2, SYMM_ROT4, SYMM_REF2, SYMM_REF2D, SYMM_REF4, |
117 | SYMM_REF4D, SYMM_REF8 }; |
ef57b17d |
118 | |
7c568a48 |
119 | enum { DIFF_BLOCK, DIFF_SIMPLE, DIFF_INTERSECT, |
120 | DIFF_SET, DIFF_RECURSIVE, DIFF_AMBIGUOUS, DIFF_IMPOSSIBLE }; |
121 | |
1d8e8ad8 |
122 | enum { |
123 | COL_BACKGROUND, |
ef57b17d |
124 | COL_GRID, |
125 | COL_CLUE, |
126 | COL_USER, |
127 | COL_HIGHLIGHT, |
7b14a9ec |
128 | COL_ERROR, |
c8266e03 |
129 | COL_PENCIL, |
ef57b17d |
130 | NCOLOURS |
1d8e8ad8 |
131 | }; |
132 | |
133 | struct game_params { |
7c568a48 |
134 | int c, r, symm, diff; |
1d8e8ad8 |
135 | }; |
136 | |
137 | struct game_state { |
138 | int c, r; |
139 | digit *grid; |
c8266e03 |
140 | unsigned char *pencil; /* c*r*c*r elements */ |
1d8e8ad8 |
141 | unsigned char *immutable; /* marks which digits are clues */ |
2ac6d24e |
142 | int completed, cheated; |
1d8e8ad8 |
143 | }; |
144 | |
145 | static game_params *default_params(void) |
146 | { |
147 | game_params *ret = snew(game_params); |
148 | |
149 | ret->c = ret->r = 3; |
ef57b17d |
150 | ret->symm = SYMM_ROT2; /* a plausible default */ |
4f36adaa |
151 | ret->diff = DIFF_BLOCK; /* so is this */ |
1d8e8ad8 |
152 | |
153 | return ret; |
154 | } |
155 | |
1d8e8ad8 |
156 | static void free_params(game_params *params) |
157 | { |
158 | sfree(params); |
159 | } |
160 | |
161 | static game_params *dup_params(game_params *params) |
162 | { |
163 | game_params *ret = snew(game_params); |
164 | *ret = *params; /* structure copy */ |
165 | return ret; |
166 | } |
167 | |
7c568a48 |
168 | static int game_fetch_preset(int i, char **name, game_params **params) |
169 | { |
170 | static struct { |
171 | char *title; |
172 | game_params params; |
173 | } presets[] = { |
174 | { "2x2 Trivial", { 2, 2, SYMM_ROT2, DIFF_BLOCK } }, |
175 | { "2x3 Basic", { 2, 3, SYMM_ROT2, DIFF_SIMPLE } }, |
4f36adaa |
176 | { "3x3 Trivial", { 3, 3, SYMM_ROT2, DIFF_BLOCK } }, |
7c568a48 |
177 | { "3x3 Basic", { 3, 3, SYMM_ROT2, DIFF_SIMPLE } }, |
178 | { "3x3 Intermediate", { 3, 3, SYMM_ROT2, DIFF_INTERSECT } }, |
179 | { "3x3 Advanced", { 3, 3, SYMM_ROT2, DIFF_SET } }, |
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180 | { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE } }, |
ab53eb64 |
181 | #ifndef SLOW_SYSTEM |
7c568a48 |
182 | { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE } }, |
183 | { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE } }, |
ab53eb64 |
184 | #endif |
7c568a48 |
185 | }; |
186 | |
187 | if (i < 0 || i >= lenof(presets)) |
188 | return FALSE; |
189 | |
190 | *name = dupstr(presets[i].title); |
191 | *params = dup_params(&presets[i].params); |
192 | |
193 | return TRUE; |
194 | } |
195 | |
1185e3c5 |
196 | static void decode_params(game_params *ret, char const *string) |
1d8e8ad8 |
197 | { |
1d8e8ad8 |
198 | ret->c = ret->r = atoi(string); |
199 | while (*string && isdigit((unsigned char)*string)) string++; |
200 | if (*string == 'x') { |
201 | string++; |
202 | ret->r = atoi(string); |
203 | while (*string && isdigit((unsigned char)*string)) string++; |
204 | } |
7c568a48 |
205 | while (*string) { |
206 | if (*string == 'r' || *string == 'm' || *string == 'a') { |
154bf9b1 |
207 | int sn, sc, sd; |
7c568a48 |
208 | sc = *string++; |
154bf9b1 |
209 | if (*string == 'd') { |
210 | sd = TRUE; |
211 | string++; |
212 | } else { |
213 | sd = FALSE; |
214 | } |
7c568a48 |
215 | sn = atoi(string); |
216 | while (*string && isdigit((unsigned char)*string)) string++; |
154bf9b1 |
217 | if (sc == 'm' && sn == 8) |
218 | ret->symm = SYMM_REF8; |
7c568a48 |
219 | if (sc == 'm' && sn == 4) |
154bf9b1 |
220 | ret->symm = sd ? SYMM_REF4D : SYMM_REF4; |
221 | if (sc == 'm' && sn == 2) |
222 | ret->symm = sd ? SYMM_REF2D : SYMM_REF2; |
7c568a48 |
223 | if (sc == 'r' && sn == 4) |
224 | ret->symm = SYMM_ROT4; |
225 | if (sc == 'r' && sn == 2) |
226 | ret->symm = SYMM_ROT2; |
227 | if (sc == 'a') |
228 | ret->symm = SYMM_NONE; |
229 | } else if (*string == 'd') { |
230 | string++; |
231 | if (*string == 't') /* trivial */ |
232 | string++, ret->diff = DIFF_BLOCK; |
233 | else if (*string == 'b') /* basic */ |
234 | string++, ret->diff = DIFF_SIMPLE; |
235 | else if (*string == 'i') /* intermediate */ |
236 | string++, ret->diff = DIFF_INTERSECT; |
237 | else if (*string == 'a') /* advanced */ |
238 | string++, ret->diff = DIFF_SET; |
de60d8bd |
239 | else if (*string == 'u') /* unreasonable */ |
240 | string++, ret->diff = DIFF_RECURSIVE; |
7c568a48 |
241 | } else |
242 | string++; /* eat unknown character */ |
ef57b17d |
243 | } |
1d8e8ad8 |
244 | } |
245 | |
1185e3c5 |
246 | static char *encode_params(game_params *params, int full) |
1d8e8ad8 |
247 | { |
248 | char str[80]; |
249 | |
250 | sprintf(str, "%dx%d", params->c, params->r); |
1185e3c5 |
251 | if (full) { |
252 | switch (params->symm) { |
154bf9b1 |
253 | case SYMM_REF8: strcat(str, "m8"); break; |
1185e3c5 |
254 | case SYMM_REF4: strcat(str, "m4"); break; |
154bf9b1 |
255 | case SYMM_REF4D: strcat(str, "md4"); break; |
256 | case SYMM_REF2: strcat(str, "m2"); break; |
257 | case SYMM_REF2D: strcat(str, "md2"); break; |
1185e3c5 |
258 | case SYMM_ROT4: strcat(str, "r4"); break; |
259 | /* case SYMM_ROT2: strcat(str, "r2"); break; [default] */ |
260 | case SYMM_NONE: strcat(str, "a"); break; |
261 | } |
262 | switch (params->diff) { |
263 | /* case DIFF_BLOCK: strcat(str, "dt"); break; [default] */ |
264 | case DIFF_SIMPLE: strcat(str, "db"); break; |
265 | case DIFF_INTERSECT: strcat(str, "di"); break; |
266 | case DIFF_SET: strcat(str, "da"); break; |
267 | case DIFF_RECURSIVE: strcat(str, "du"); break; |
268 | } |
269 | } |
1d8e8ad8 |
270 | return dupstr(str); |
271 | } |
272 | |
273 | static config_item *game_configure(game_params *params) |
274 | { |
275 | config_item *ret; |
276 | char buf[80]; |
277 | |
278 | ret = snewn(5, config_item); |
279 | |
280 | ret[0].name = "Columns of sub-blocks"; |
281 | ret[0].type = C_STRING; |
282 | sprintf(buf, "%d", params->c); |
283 | ret[0].sval = dupstr(buf); |
284 | ret[0].ival = 0; |
285 | |
286 | ret[1].name = "Rows of sub-blocks"; |
287 | ret[1].type = C_STRING; |
288 | sprintf(buf, "%d", params->r); |
289 | ret[1].sval = dupstr(buf); |
290 | ret[1].ival = 0; |
291 | |
ef57b17d |
292 | ret[2].name = "Symmetry"; |
293 | ret[2].type = C_CHOICES; |
154bf9b1 |
294 | ret[2].sval = ":None:2-way rotation:4-way rotation:2-way mirror:" |
295 | "2-way diagonal mirror:4-way mirror:4-way diagonal mirror:" |
296 | "8-way mirror"; |
ef57b17d |
297 | ret[2].ival = params->symm; |
298 | |
7c568a48 |
299 | ret[3].name = "Difficulty"; |
300 | ret[3].type = C_CHOICES; |
de60d8bd |
301 | ret[3].sval = ":Trivial:Basic:Intermediate:Advanced:Unreasonable"; |
7c568a48 |
302 | ret[3].ival = params->diff; |
1d8e8ad8 |
303 | |
7c568a48 |
304 | ret[4].name = NULL; |
305 | ret[4].type = C_END; |
306 | ret[4].sval = NULL; |
307 | ret[4].ival = 0; |
1d8e8ad8 |
308 | |
309 | return ret; |
310 | } |
311 | |
312 | static game_params *custom_params(config_item *cfg) |
313 | { |
314 | game_params *ret = snew(game_params); |
315 | |
c1f743c8 |
316 | ret->c = atoi(cfg[0].sval); |
317 | ret->r = atoi(cfg[1].sval); |
ef57b17d |
318 | ret->symm = cfg[2].ival; |
7c568a48 |
319 | ret->diff = cfg[3].ival; |
1d8e8ad8 |
320 | |
321 | return ret; |
322 | } |
323 | |
324 | static char *validate_params(game_params *params) |
325 | { |
326 | if (params->c < 2 || params->r < 2) |
327 | return "Both dimensions must be at least 2"; |
328 | if (params->c > ORDER_MAX || params->r > ORDER_MAX) |
329 | return "Dimensions greater than "STR(ORDER_MAX)" are not supported"; |
330 | return NULL; |
331 | } |
332 | |
333 | /* ---------------------------------------------------------------------- |
334 | * Full recursive Solo solver. |
335 | * |
336 | * The algorithm for this solver is shamelessly copied from a |
337 | * Python solver written by Andrew Wilkinson (which is GPLed, but |
338 | * I've reused only ideas and no code). It mostly just does the |
339 | * obvious recursive thing: pick an empty square, put one of the |
340 | * possible digits in it, recurse until all squares are filled, |
341 | * backtrack and change some choices if necessary. |
342 | * |
343 | * The clever bit is that every time it chooses which square to |
344 | * fill in next, it does so by counting the number of _possible_ |
345 | * numbers that can go in each square, and it prioritises so that |
346 | * it picks a square with the _lowest_ number of possibilities. The |
347 | * idea is that filling in lots of the obvious bits (particularly |
348 | * any squares with only one possibility) will cut down on the list |
349 | * of possibilities for other squares and hence reduce the enormous |
350 | * search space as much as possible as early as possible. |
351 | * |
352 | * In practice the algorithm appeared to work very well; run on |
353 | * sample problems from the Times it completed in well under a |
354 | * second on my G5 even when written in Python, and given an empty |
355 | * grid (so that in principle it would enumerate _all_ solved |
356 | * grids!) it found the first valid solution just as quickly. So |
357 | * with a bit more randomisation I see no reason not to use this as |
358 | * my grid generator. |
359 | */ |
360 | |
361 | /* |
362 | * Internal data structure used in solver to keep track of |
363 | * progress. |
364 | */ |
365 | struct rsolve_coord { int x, y, r; }; |
366 | struct rsolve_usage { |
367 | int c, r, cr; /* cr == c*r */ |
368 | /* grid is a copy of the input grid, modified as we go along */ |
369 | digit *grid; |
370 | /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ |
371 | unsigned char *row; |
372 | /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ |
373 | unsigned char *col; |
374 | /* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */ |
375 | unsigned char *blk; |
376 | /* This lists all the empty spaces remaining in the grid. */ |
377 | struct rsolve_coord *spaces; |
378 | int nspaces; |
379 | /* If we need randomisation in the solve, this is our random state. */ |
380 | random_state *rs; |
381 | /* Number of solutions so far found, and maximum number we care about. */ |
382 | int solns, maxsolns; |
383 | }; |
384 | |
385 | /* |
386 | * The real recursive step in the solving function. |
387 | */ |
388 | static void rsolve_real(struct rsolve_usage *usage, digit *grid) |
389 | { |
390 | int c = usage->c, r = usage->r, cr = usage->cr; |
391 | int i, j, n, sx, sy, bestm, bestr; |
392 | int *digits; |
393 | |
394 | /* |
395 | * Firstly, check for completion! If there are no spaces left |
396 | * in the grid, we have a solution. |
397 | */ |
398 | if (usage->nspaces == 0) { |
399 | if (!usage->solns) { |
400 | /* |
401 | * This is our first solution, so fill in the output grid. |
402 | */ |
403 | memcpy(grid, usage->grid, cr * cr); |
404 | } |
405 | usage->solns++; |
406 | return; |
407 | } |
408 | |
409 | /* |
410 | * Otherwise, there must be at least one space. Find the most |
411 | * constrained space, using the `r' field as a tie-breaker. |
412 | */ |
413 | bestm = cr+1; /* so that any space will beat it */ |
414 | bestr = 0; |
415 | i = sx = sy = -1; |
416 | for (j = 0; j < usage->nspaces; j++) { |
417 | int x = usage->spaces[j].x, y = usage->spaces[j].y; |
418 | int m; |
419 | |
420 | /* |
421 | * Find the number of digits that could go in this space. |
422 | */ |
423 | m = 0; |
424 | for (n = 0; n < cr; n++) |
425 | if (!usage->row[y*cr+n] && !usage->col[x*cr+n] && |
426 | !usage->blk[((y/c)*c+(x/r))*cr+n]) |
427 | m++; |
428 | |
429 | if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) { |
430 | bestm = m; |
431 | bestr = usage->spaces[j].r; |
432 | sx = x; |
433 | sy = y; |
434 | i = j; |
435 | } |
436 | } |
437 | |
438 | /* |
439 | * Swap that square into the final place in the spaces array, |
440 | * so that decrementing nspaces will remove it from the list. |
441 | */ |
442 | if (i != usage->nspaces-1) { |
443 | struct rsolve_coord t; |
444 | t = usage->spaces[usage->nspaces-1]; |
445 | usage->spaces[usage->nspaces-1] = usage->spaces[i]; |
446 | usage->spaces[i] = t; |
447 | } |
448 | |
449 | /* |
450 | * Now we've decided which square to start our recursion at, |
451 | * simply go through all possible values, shuffling them |
452 | * randomly first if necessary. |
453 | */ |
454 | digits = snewn(bestm, int); |
455 | j = 0; |
456 | for (n = 0; n < cr; n++) |
457 | if (!usage->row[sy*cr+n] && !usage->col[sx*cr+n] && |
458 | !usage->blk[((sy/c)*c+(sx/r))*cr+n]) { |
459 | digits[j++] = n+1; |
460 | } |
461 | |
462 | if (usage->rs) { |
463 | /* shuffle */ |
464 | for (i = j; i > 1; i--) { |
465 | int p = random_upto(usage->rs, i); |
466 | if (p != i-1) { |
467 | int t = digits[p]; |
468 | digits[p] = digits[i-1]; |
469 | digits[i-1] = t; |
470 | } |
471 | } |
472 | } |
473 | |
474 | /* And finally, go through the digit list and actually recurse. */ |
475 | for (i = 0; i < j; i++) { |
476 | n = digits[i]; |
477 | |
478 | /* Update the usage structure to reflect the placing of this digit. */ |
479 | usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = |
480 | usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = TRUE; |
481 | usage->grid[sy*cr+sx] = n; |
482 | usage->nspaces--; |
483 | |
484 | /* Call the solver recursively. */ |
485 | rsolve_real(usage, grid); |
486 | |
487 | /* |
488 | * If we have seen as many solutions as we need, terminate |
489 | * all processing immediately. |
490 | */ |
491 | if (usage->solns >= usage->maxsolns) |
492 | break; |
493 | |
494 | /* Revert the usage structure. */ |
495 | usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = |
496 | usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = FALSE; |
497 | usage->grid[sy*cr+sx] = 0; |
498 | usage->nspaces++; |
499 | } |
500 | |
501 | sfree(digits); |
502 | } |
503 | |
504 | /* |
505 | * Entry point to solver. You give it dimensions and a starting |
506 | * grid, which is simply an array of N^4 digits. In that array, 0 |
507 | * means an empty square, and 1..N mean a clue square. |
508 | * |
509 | * Return value is the number of solutions found; searching will |
510 | * stop after the provided `max'. (Thus, you can pass max==1 to |
511 | * indicate that you only care about finding _one_ solution, or |
512 | * max==2 to indicate that you want to know the difference between |
513 | * a unique and non-unique solution.) The input parameter `grid' is |
514 | * also filled in with the _first_ (or only) solution found by the |
515 | * solver. |
516 | */ |
517 | static int rsolve(int c, int r, digit *grid, random_state *rs, int max) |
518 | { |
519 | struct rsolve_usage *usage; |
520 | int x, y, cr = c*r; |
521 | int ret; |
522 | |
523 | /* |
524 | * Create an rsolve_usage structure. |
525 | */ |
526 | usage = snew(struct rsolve_usage); |
527 | |
528 | usage->c = c; |
529 | usage->r = r; |
530 | usage->cr = cr; |
531 | |
532 | usage->grid = snewn(cr * cr, digit); |
533 | memcpy(usage->grid, grid, cr * cr); |
534 | |
535 | usage->row = snewn(cr * cr, unsigned char); |
536 | usage->col = snewn(cr * cr, unsigned char); |
537 | usage->blk = snewn(cr * cr, unsigned char); |
538 | memset(usage->row, FALSE, cr * cr); |
539 | memset(usage->col, FALSE, cr * cr); |
540 | memset(usage->blk, FALSE, cr * cr); |
541 | |
542 | usage->spaces = snewn(cr * cr, struct rsolve_coord); |
543 | usage->nspaces = 0; |
544 | |
545 | usage->solns = 0; |
546 | usage->maxsolns = max; |
547 | |
548 | usage->rs = rs; |
549 | |
550 | /* |
551 | * Now fill it in with data from the input grid. |
552 | */ |
553 | for (y = 0; y < cr; y++) { |
554 | for (x = 0; x < cr; x++) { |
555 | int v = grid[y*cr+x]; |
556 | if (v == 0) { |
557 | usage->spaces[usage->nspaces].x = x; |
558 | usage->spaces[usage->nspaces].y = y; |
559 | if (rs) |
560 | usage->spaces[usage->nspaces].r = random_bits(rs, 31); |
561 | else |
562 | usage->spaces[usage->nspaces].r = usage->nspaces; |
563 | usage->nspaces++; |
564 | } else { |
565 | usage->row[y*cr+v-1] = TRUE; |
566 | usage->col[x*cr+v-1] = TRUE; |
567 | usage->blk[((y/c)*c+(x/r))*cr+v-1] = TRUE; |
568 | } |
569 | } |
570 | } |
571 | |
572 | /* |
573 | * Run the real recursive solving function. |
574 | */ |
575 | rsolve_real(usage, grid); |
576 | ret = usage->solns; |
577 | |
578 | /* |
579 | * Clean up the usage structure now we have our answer. |
580 | */ |
581 | sfree(usage->spaces); |
582 | sfree(usage->blk); |
583 | sfree(usage->col); |
584 | sfree(usage->row); |
585 | sfree(usage->grid); |
586 | sfree(usage); |
587 | |
588 | /* |
589 | * And return. |
590 | */ |
591 | return ret; |
592 | } |
593 | |
594 | /* ---------------------------------------------------------------------- |
595 | * End of recursive solver code. |
596 | */ |
597 | |
598 | /* ---------------------------------------------------------------------- |
599 | * Less capable non-recursive solver. This one is used to check |
600 | * solubility of a grid as we gradually remove numbers from it: by |
601 | * verifying a grid using this solver we can ensure it isn't _too_ |
602 | * hard (e.g. does not actually require guessing and backtracking). |
603 | * |
604 | * It supports a variety of specific modes of reasoning. By |
605 | * enabling or disabling subsets of these modes we can arrange a |
606 | * range of difficulty levels. |
607 | */ |
608 | |
609 | /* |
610 | * Modes of reasoning currently supported: |
611 | * |
612 | * - Positional elimination: a number must go in a particular |
613 | * square because all the other empty squares in a given |
614 | * row/col/blk are ruled out. |
615 | * |
616 | * - Numeric elimination: a square must have a particular number |
617 | * in because all the other numbers that could go in it are |
618 | * ruled out. |
619 | * |
7c568a48 |
620 | * - Intersectional analysis: given two domains which overlap |
1d8e8ad8 |
621 | * (hence one must be a block, and the other can be a row or |
622 | * col), if the possible locations for a particular number in |
623 | * one of the domains can be narrowed down to the overlap, then |
624 | * that number can be ruled out everywhere but the overlap in |
625 | * the other domain too. |
626 | * |
7c568a48 |
627 | * - Set elimination: if there is a subset of the empty squares |
628 | * within a domain such that the union of the possible numbers |
629 | * in that subset has the same size as the subset itself, then |
630 | * those numbers can be ruled out everywhere else in the domain. |
631 | * (For example, if there are five empty squares and the |
632 | * possible numbers in each are 12, 23, 13, 134 and 1345, then |
633 | * the first three empty squares form such a subset: the numbers |
634 | * 1, 2 and 3 _must_ be in those three squares in some |
635 | * permutation, and hence we can deduce none of them can be in |
636 | * the fourth or fifth squares.) |
637 | * + You can also see this the other way round, concentrating |
638 | * on numbers rather than squares: if there is a subset of |
639 | * the unplaced numbers within a domain such that the union |
640 | * of all their possible positions has the same size as the |
641 | * subset itself, then all other numbers can be ruled out for |
642 | * those positions. However, it turns out that this is |
643 | * exactly equivalent to the first formulation at all times: |
644 | * there is a 1-1 correspondence between suitable subsets of |
645 | * the unplaced numbers and suitable subsets of the unfilled |
646 | * places, found by taking the _complement_ of the union of |
647 | * the numbers' possible positions (or the spaces' possible |
648 | * contents). |
1d8e8ad8 |
649 | */ |
650 | |
4846f788 |
651 | /* |
652 | * Within this solver, I'm going to transform all y-coordinates by |
653 | * inverting the significance of the block number and the position |
654 | * within the block. That is, we will start with the top row of |
655 | * each block in order, then the second row of each block in order, |
656 | * etc. |
657 | * |
658 | * This transformation has the enormous advantage that it means |
659 | * every row, column _and_ block is described by an arithmetic |
660 | * progression of coordinates within the cubic array, so that I can |
661 | * use the same very simple function to do blockwise, row-wise and |
662 | * column-wise elimination. |
663 | */ |
664 | #define YTRANS(y) (((y)%c)*r+(y)/c) |
665 | #define YUNTRANS(y) (((y)%r)*c+(y)/r) |
666 | |
1d8e8ad8 |
667 | struct nsolve_usage { |
668 | int c, r, cr; |
669 | /* |
670 | * We set up a cubic array, indexed by x, y and digit; each |
671 | * element of this array is TRUE or FALSE according to whether |
672 | * or not that digit _could_ in principle go in that position. |
673 | * |
674 | * The way to index this array is cube[(x*cr+y)*cr+n-1]. |
4846f788 |
675 | * y-coordinates in here are transformed. |
1d8e8ad8 |
676 | */ |
677 | unsigned char *cube; |
678 | /* |
679 | * This is the grid in which we write down our final |
4846f788 |
680 | * deductions. y-coordinates in here are _not_ transformed. |
1d8e8ad8 |
681 | */ |
682 | digit *grid; |
683 | /* |
684 | * Now we keep track, at a slightly higher level, of what we |
685 | * have yet to work out, to prevent doing the same deduction |
686 | * many times. |
687 | */ |
688 | /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ |
689 | unsigned char *row; |
690 | /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ |
691 | unsigned char *col; |
692 | /* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */ |
693 | unsigned char *blk; |
694 | }; |
4846f788 |
695 | #define cubepos(x,y,n) (((x)*usage->cr+(y))*usage->cr+(n)-1) |
696 | #define cube(x,y,n) (usage->cube[cubepos(x,y,n)]) |
1d8e8ad8 |
697 | |
698 | /* |
699 | * Function called when we are certain that a particular square has |
4846f788 |
700 | * a particular number in it. The y-coordinate passed in here is |
701 | * transformed. |
1d8e8ad8 |
702 | */ |
703 | static void nsolve_place(struct nsolve_usage *usage, int x, int y, int n) |
704 | { |
705 | int c = usage->c, r = usage->r, cr = usage->cr; |
706 | int i, j, bx, by; |
707 | |
708 | assert(cube(x,y,n)); |
709 | |
710 | /* |
711 | * Rule out all other numbers in this square. |
712 | */ |
713 | for (i = 1; i <= cr; i++) |
714 | if (i != n) |
715 | cube(x,y,i) = FALSE; |
716 | |
717 | /* |
718 | * Rule out this number in all other positions in the row. |
719 | */ |
720 | for (i = 0; i < cr; i++) |
721 | if (i != y) |
722 | cube(x,i,n) = FALSE; |
723 | |
724 | /* |
725 | * Rule out this number in all other positions in the column. |
726 | */ |
727 | for (i = 0; i < cr; i++) |
728 | if (i != x) |
729 | cube(i,y,n) = FALSE; |
730 | |
731 | /* |
732 | * Rule out this number in all other positions in the block. |
733 | */ |
734 | bx = (x/r)*r; |
4846f788 |
735 | by = y % r; |
1d8e8ad8 |
736 | for (i = 0; i < r; i++) |
737 | for (j = 0; j < c; j++) |
4846f788 |
738 | if (bx+i != x || by+j*r != y) |
739 | cube(bx+i,by+j*r,n) = FALSE; |
1d8e8ad8 |
740 | |
741 | /* |
742 | * Enter the number in the result grid. |
743 | */ |
4846f788 |
744 | usage->grid[YUNTRANS(y)*cr+x] = n; |
1d8e8ad8 |
745 | |
746 | /* |
747 | * Cross out this number from the list of numbers left to place |
748 | * in its row, its column and its block. |
749 | */ |
750 | usage->row[y*cr+n-1] = usage->col[x*cr+n-1] = |
7c568a48 |
751 | usage->blk[((y%r)*c+(x/r))*cr+n-1] = TRUE; |
1d8e8ad8 |
752 | } |
753 | |
7c568a48 |
754 | static int nsolve_elim(struct nsolve_usage *usage, int start, int step |
755 | #ifdef STANDALONE_SOLVER |
756 | , char *fmt, ... |
757 | #endif |
758 | ) |
1d8e8ad8 |
759 | { |
4846f788 |
760 | int c = usage->c, r = usage->r, cr = c*r; |
761 | int fpos, m, i; |
1d8e8ad8 |
762 | |
763 | /* |
4846f788 |
764 | * Count the number of set bits within this section of the |
765 | * cube. |
1d8e8ad8 |
766 | */ |
767 | m = 0; |
4846f788 |
768 | fpos = -1; |
769 | for (i = 0; i < cr; i++) |
770 | if (usage->cube[start+i*step]) { |
771 | fpos = start+i*step; |
1d8e8ad8 |
772 | m++; |
773 | } |
774 | |
775 | if (m == 1) { |
4846f788 |
776 | int x, y, n; |
777 | assert(fpos >= 0); |
1d8e8ad8 |
778 | |
4846f788 |
779 | n = 1 + fpos % cr; |
780 | y = fpos / cr; |
781 | x = y / cr; |
782 | y %= cr; |
1d8e8ad8 |
783 | |
3ddae0ff |
784 | if (!usage->grid[YUNTRANS(y)*cr+x]) { |
7c568a48 |
785 | #ifdef STANDALONE_SOLVER |
786 | if (solver_show_working) { |
787 | va_list ap; |
788 | va_start(ap, fmt); |
789 | vprintf(fmt, ap); |
790 | va_end(ap); |
791 | printf(":\n placing %d at (%d,%d)\n", |
792 | n, 1+x, 1+YUNTRANS(y)); |
793 | } |
794 | #endif |
3ddae0ff |
795 | nsolve_place(usage, x, y, n); |
796 | return TRUE; |
797 | } |
1d8e8ad8 |
798 | } |
799 | |
800 | return FALSE; |
801 | } |
802 | |
7c568a48 |
803 | static int nsolve_intersect(struct nsolve_usage *usage, |
804 | int start1, int step1, int start2, int step2 |
805 | #ifdef STANDALONE_SOLVER |
806 | , char *fmt, ... |
807 | #endif |
808 | ) |
809 | { |
810 | int c = usage->c, r = usage->r, cr = c*r; |
811 | int ret, i; |
812 | |
813 | /* |
814 | * Loop over the first domain and see if there's any set bit |
815 | * not also in the second. |
816 | */ |
817 | for (i = 0; i < cr; i++) { |
818 | int p = start1+i*step1; |
819 | if (usage->cube[p] && |
820 | !(p >= start2 && p < start2+cr*step2 && |
821 | (p - start2) % step2 == 0)) |
822 | return FALSE; /* there is, so we can't deduce */ |
823 | } |
824 | |
825 | /* |
826 | * We have determined that all set bits in the first domain are |
827 | * within its overlap with the second. So loop over the second |
828 | * domain and remove all set bits that aren't also in that |
829 | * overlap; return TRUE iff we actually _did_ anything. |
830 | */ |
831 | ret = FALSE; |
832 | for (i = 0; i < cr; i++) { |
833 | int p = start2+i*step2; |
834 | if (usage->cube[p] && |
835 | !(p >= start1 && p < start1+cr*step1 && (p - start1) % step1 == 0)) |
836 | { |
837 | #ifdef STANDALONE_SOLVER |
838 | if (solver_show_working) { |
839 | int px, py, pn; |
840 | |
841 | if (!ret) { |
842 | va_list ap; |
843 | va_start(ap, fmt); |
844 | vprintf(fmt, ap); |
845 | va_end(ap); |
846 | printf(":\n"); |
847 | } |
848 | |
849 | pn = 1 + p % cr; |
850 | py = p / cr; |
851 | px = py / cr; |
852 | py %= cr; |
853 | |
854 | printf(" ruling out %d at (%d,%d)\n", |
855 | pn, 1+px, 1+YUNTRANS(py)); |
856 | } |
857 | #endif |
858 | ret = TRUE; /* we did something */ |
859 | usage->cube[p] = 0; |
860 | } |
861 | } |
862 | |
863 | return ret; |
864 | } |
865 | |
ab53eb64 |
866 | struct nsolve_scratch { |
867 | unsigned char *grid, *rowidx, *colidx, *set; |
868 | }; |
869 | |
7c568a48 |
870 | static int nsolve_set(struct nsolve_usage *usage, |
ab53eb64 |
871 | struct nsolve_scratch *scratch, |
7c568a48 |
872 | int start, int step1, int step2 |
873 | #ifdef STANDALONE_SOLVER |
874 | , char *fmt, ... |
875 | #endif |
876 | ) |
877 | { |
878 | int c = usage->c, r = usage->r, cr = c*r; |
879 | int i, j, n, count; |
ab53eb64 |
880 | unsigned char *grid = scratch->grid; |
881 | unsigned char *rowidx = scratch->rowidx; |
882 | unsigned char *colidx = scratch->colidx; |
883 | unsigned char *set = scratch->set; |
7c568a48 |
884 | |
885 | /* |
886 | * We are passed a cr-by-cr matrix of booleans. Our first job |
887 | * is to winnow it by finding any definite placements - i.e. |
888 | * any row with a solitary 1 - and discarding that row and the |
889 | * column containing the 1. |
890 | */ |
891 | memset(rowidx, TRUE, cr); |
892 | memset(colidx, TRUE, cr); |
893 | for (i = 0; i < cr; i++) { |
894 | int count = 0, first = -1; |
895 | for (j = 0; j < cr; j++) |
896 | if (usage->cube[start+i*step1+j*step2]) |
897 | first = j, count++; |
898 | if (count == 0) { |
899 | /* |
900 | * This condition actually marks a completely insoluble |
901 | * (i.e. internally inconsistent) puzzle. We return and |
902 | * report no progress made. |
903 | */ |
904 | return FALSE; |
905 | } |
906 | if (count == 1) |
907 | rowidx[i] = colidx[first] = FALSE; |
908 | } |
909 | |
910 | /* |
911 | * Convert each of rowidx/colidx from a list of 0s and 1s to a |
912 | * list of the indices of the 1s. |
913 | */ |
914 | for (i = j = 0; i < cr; i++) |
915 | if (rowidx[i]) |
916 | rowidx[j++] = i; |
917 | n = j; |
918 | for (i = j = 0; i < cr; i++) |
919 | if (colidx[i]) |
920 | colidx[j++] = i; |
921 | assert(n == j); |
922 | |
923 | /* |
924 | * And create the smaller matrix. |
925 | */ |
926 | for (i = 0; i < n; i++) |
927 | for (j = 0; j < n; j++) |
928 | grid[i*cr+j] = usage->cube[start+rowidx[i]*step1+colidx[j]*step2]; |
929 | |
930 | /* |
931 | * Having done that, we now have a matrix in which every row |
932 | * has at least two 1s in. Now we search to see if we can find |
933 | * a rectangle of zeroes (in the set-theoretic sense of |
934 | * `rectangle', i.e. a subset of rows crossed with a subset of |
935 | * columns) whose width and height add up to n. |
936 | */ |
937 | |
938 | memset(set, 0, n); |
939 | count = 0; |
940 | while (1) { |
941 | /* |
942 | * We have a candidate set. If its size is <=1 or >=n-1 |
943 | * then we move on immediately. |
944 | */ |
945 | if (count > 1 && count < n-1) { |
946 | /* |
947 | * The number of rows we need is n-count. See if we can |
948 | * find that many rows which each have a zero in all |
949 | * the positions listed in `set'. |
950 | */ |
951 | int rows = 0; |
952 | for (i = 0; i < n; i++) { |
953 | int ok = TRUE; |
954 | for (j = 0; j < n; j++) |
955 | if (set[j] && grid[i*cr+j]) { |
956 | ok = FALSE; |
957 | break; |
958 | } |
959 | if (ok) |
960 | rows++; |
961 | } |
962 | |
963 | /* |
964 | * We expect never to be able to get _more_ than |
965 | * n-count suitable rows: this would imply that (for |
966 | * example) there are four numbers which between them |
967 | * have at most three possible positions, and hence it |
968 | * indicates a faulty deduction before this point or |
969 | * even a bogus clue. |
970 | */ |
971 | assert(rows <= n - count); |
972 | if (rows >= n - count) { |
973 | int progress = FALSE; |
974 | |
975 | /* |
976 | * We've got one! Now, for each row which _doesn't_ |
977 | * satisfy the criterion, eliminate all its set |
978 | * bits in the positions _not_ listed in `set'. |
979 | * Return TRUE (meaning progress has been made) if |
980 | * we successfully eliminated anything at all. |
981 | * |
982 | * This involves referring back through |
983 | * rowidx/colidx in order to work out which actual |
984 | * positions in the cube to meddle with. |
985 | */ |
986 | for (i = 0; i < n; i++) { |
987 | int ok = TRUE; |
988 | for (j = 0; j < n; j++) |
989 | if (set[j] && grid[i*cr+j]) { |
990 | ok = FALSE; |
991 | break; |
992 | } |
993 | if (!ok) { |
994 | for (j = 0; j < n; j++) |
995 | if (!set[j] && grid[i*cr+j]) { |
996 | int fpos = (start+rowidx[i]*step1+ |
997 | colidx[j]*step2); |
998 | #ifdef STANDALONE_SOLVER |
999 | if (solver_show_working) { |
1000 | int px, py, pn; |
1001 | |
1002 | if (!progress) { |
1003 | va_list ap; |
1004 | va_start(ap, fmt); |
1005 | vprintf(fmt, ap); |
1006 | va_end(ap); |
1007 | printf(":\n"); |
1008 | } |
1009 | |
1010 | pn = 1 + fpos % cr; |
1011 | py = fpos / cr; |
1012 | px = py / cr; |
1013 | py %= cr; |
1014 | |
1015 | printf(" ruling out %d at (%d,%d)\n", |
1016 | pn, 1+px, 1+YUNTRANS(py)); |
1017 | } |
1018 | #endif |
1019 | progress = TRUE; |
1020 | usage->cube[fpos] = FALSE; |
1021 | } |
1022 | } |
1023 | } |
1024 | |
1025 | if (progress) { |
7c568a48 |
1026 | return TRUE; |
1027 | } |
1028 | } |
1029 | } |
1030 | |
1031 | /* |
1032 | * Binary increment: change the rightmost 0 to a 1, and |
1033 | * change all 1s to the right of it to 0s. |
1034 | */ |
1035 | i = n; |
1036 | while (i > 0 && set[i-1]) |
1037 | set[--i] = 0, count--; |
1038 | if (i > 0) |
1039 | set[--i] = 1, count++; |
1040 | else |
1041 | break; /* done */ |
1042 | } |
1043 | |
7c568a48 |
1044 | return FALSE; |
1045 | } |
1046 | |
ab53eb64 |
1047 | static struct nsolve_scratch *nsolve_new_scratch(struct nsolve_usage *usage) |
1048 | { |
1049 | struct nsolve_scratch *scratch = snew(struct nsolve_scratch); |
1050 | int cr = usage->cr; |
1051 | scratch->grid = snewn(cr*cr, unsigned char); |
1052 | scratch->rowidx = snewn(cr, unsigned char); |
1053 | scratch->colidx = snewn(cr, unsigned char); |
1054 | scratch->set = snewn(cr, unsigned char); |
1055 | return scratch; |
1056 | } |
1057 | |
1058 | static void nsolve_free_scratch(struct nsolve_scratch *scratch) |
1059 | { |
1060 | sfree(scratch->set); |
1061 | sfree(scratch->colidx); |
1062 | sfree(scratch->rowidx); |
1063 | sfree(scratch->grid); |
1064 | sfree(scratch); |
1065 | } |
1066 | |
1d8e8ad8 |
1067 | static int nsolve(int c, int r, digit *grid) |
1068 | { |
1069 | struct nsolve_usage *usage; |
ab53eb64 |
1070 | struct nsolve_scratch *scratch; |
1d8e8ad8 |
1071 | int cr = c*r; |
1072 | int x, y, n; |
7c568a48 |
1073 | int diff = DIFF_BLOCK; |
1d8e8ad8 |
1074 | |
1075 | /* |
1076 | * Set up a usage structure as a clean slate (everything |
1077 | * possible). |
1078 | */ |
1079 | usage = snew(struct nsolve_usage); |
1080 | usage->c = c; |
1081 | usage->r = r; |
1082 | usage->cr = cr; |
1083 | usage->cube = snewn(cr*cr*cr, unsigned char); |
1084 | usage->grid = grid; /* write straight back to the input */ |
1085 | memset(usage->cube, TRUE, cr*cr*cr); |
1086 | |
1087 | usage->row = snewn(cr * cr, unsigned char); |
1088 | usage->col = snewn(cr * cr, unsigned char); |
1089 | usage->blk = snewn(cr * cr, unsigned char); |
1090 | memset(usage->row, FALSE, cr * cr); |
1091 | memset(usage->col, FALSE, cr * cr); |
1092 | memset(usage->blk, FALSE, cr * cr); |
1093 | |
ab53eb64 |
1094 | scratch = nsolve_new_scratch(usage); |
1095 | |
1d8e8ad8 |
1096 | /* |
1097 | * Place all the clue numbers we are given. |
1098 | */ |
1099 | for (x = 0; x < cr; x++) |
1100 | for (y = 0; y < cr; y++) |
1101 | if (grid[y*cr+x]) |
4846f788 |
1102 | nsolve_place(usage, x, YTRANS(y), grid[y*cr+x]); |
1d8e8ad8 |
1103 | |
1104 | /* |
1105 | * Now loop over the grid repeatedly trying all permitted modes |
1106 | * of reasoning. The loop terminates if we complete an |
1107 | * iteration without making any progress; we then return |
1108 | * failure or success depending on whether the grid is full or |
1109 | * not. |
1110 | */ |
1111 | while (1) { |
7c568a48 |
1112 | /* |
1113 | * I'd like to write `continue;' inside each of the |
1114 | * following loops, so that the solver returns here after |
1115 | * making some progress. However, I can't specify that I |
1116 | * want to continue an outer loop rather than the innermost |
1117 | * one, so I'm apologetically resorting to a goto. |
1118 | */ |
3ddae0ff |
1119 | cont: |
1120 | |
1d8e8ad8 |
1121 | /* |
1122 | * Blockwise positional elimination. |
1123 | */ |
4846f788 |
1124 | for (x = 0; x < cr; x += r) |
1d8e8ad8 |
1125 | for (y = 0; y < r; y++) |
1126 | for (n = 1; n <= cr; n++) |
4846f788 |
1127 | if (!usage->blk[(y*c+(x/r))*cr+n-1] && |
7c568a48 |
1128 | nsolve_elim(usage, cubepos(x,y,n), r*cr |
1129 | #ifdef STANDALONE_SOLVER |
1130 | , "positional elimination," |
1131 | " block (%d,%d)", 1+x/r, 1+y |
1132 | #endif |
1133 | )) { |
1134 | diff = max(diff, DIFF_BLOCK); |
3ddae0ff |
1135 | goto cont; |
7c568a48 |
1136 | } |
1d8e8ad8 |
1137 | |
1138 | /* |
1139 | * Row-wise positional elimination. |
1140 | */ |
1141 | for (y = 0; y < cr; y++) |
1142 | for (n = 1; n <= cr; n++) |
1143 | if (!usage->row[y*cr+n-1] && |
7c568a48 |
1144 | nsolve_elim(usage, cubepos(0,y,n), cr*cr |
1145 | #ifdef STANDALONE_SOLVER |
1146 | , "positional elimination," |
1147 | " row %d", 1+YUNTRANS(y) |
1148 | #endif |
1149 | )) { |
1150 | diff = max(diff, DIFF_SIMPLE); |
3ddae0ff |
1151 | goto cont; |
7c568a48 |
1152 | } |
1d8e8ad8 |
1153 | /* |
1154 | * Column-wise positional elimination. |
1155 | */ |
1156 | for (x = 0; x < cr; x++) |
1157 | for (n = 1; n <= cr; n++) |
1158 | if (!usage->col[x*cr+n-1] && |
7c568a48 |
1159 | nsolve_elim(usage, cubepos(x,0,n), cr |
1160 | #ifdef STANDALONE_SOLVER |
1161 | , "positional elimination," " column %d", 1+x |
1162 | #endif |
1163 | )) { |
1164 | diff = max(diff, DIFF_SIMPLE); |
3ddae0ff |
1165 | goto cont; |
7c568a48 |
1166 | } |
1d8e8ad8 |
1167 | |
1168 | /* |
1169 | * Numeric elimination. |
1170 | */ |
1171 | for (x = 0; x < cr; x++) |
1172 | for (y = 0; y < cr; y++) |
4846f788 |
1173 | if (!usage->grid[YUNTRANS(y)*cr+x] && |
7c568a48 |
1174 | nsolve_elim(usage, cubepos(x,y,1), 1 |
1175 | #ifdef STANDALONE_SOLVER |
1176 | , "numeric elimination at (%d,%d)", 1+x, |
1177 | 1+YUNTRANS(y) |
1178 | #endif |
1179 | )) { |
1180 | diff = max(diff, DIFF_SIMPLE); |
1181 | goto cont; |
1182 | } |
1183 | |
1184 | /* |
1185 | * Intersectional analysis, rows vs blocks. |
1186 | */ |
1187 | for (y = 0; y < cr; y++) |
1188 | for (x = 0; x < cr; x += r) |
1189 | for (n = 1; n <= cr; n++) |
1190 | if (!usage->row[y*cr+n-1] && |
1191 | !usage->blk[((y%r)*c+(x/r))*cr+n-1] && |
1192 | (nsolve_intersect(usage, cubepos(0,y,n), cr*cr, |
1193 | cubepos(x,y%r,n), r*cr |
1194 | #ifdef STANDALONE_SOLVER |
1195 | , "intersectional analysis," |
1196 | " row %d vs block (%d,%d)", |
b37c4d5f |
1197 | 1+YUNTRANS(y), 1+x/r, 1+y%r |
7c568a48 |
1198 | #endif |
1199 | ) || |
1200 | nsolve_intersect(usage, cubepos(x,y%r,n), r*cr, |
1201 | cubepos(0,y,n), cr*cr |
1202 | #ifdef STANDALONE_SOLVER |
1203 | , "intersectional analysis," |
1204 | " block (%d,%d) vs row %d", |
b37c4d5f |
1205 | 1+x/r, 1+y%r, 1+YUNTRANS(y) |
7c568a48 |
1206 | #endif |
1207 | ))) { |
1208 | diff = max(diff, DIFF_INTERSECT); |
1209 | goto cont; |
1210 | } |
1211 | |
1212 | /* |
1213 | * Intersectional analysis, columns vs blocks. |
1214 | */ |
1215 | for (x = 0; x < cr; x++) |
1216 | for (y = 0; y < r; y++) |
1217 | for (n = 1; n <= cr; n++) |
1218 | if (!usage->col[x*cr+n-1] && |
1219 | !usage->blk[(y*c+(x/r))*cr+n-1] && |
1220 | (nsolve_intersect(usage, cubepos(x,0,n), cr, |
1221 | cubepos((x/r)*r,y,n), r*cr |
1222 | #ifdef STANDALONE_SOLVER |
1223 | , "intersectional analysis," |
1224 | " column %d vs block (%d,%d)", |
1225 | 1+x, 1+x/r, 1+y |
1226 | #endif |
1227 | ) || |
1228 | nsolve_intersect(usage, cubepos((x/r)*r,y,n), r*cr, |
1229 | cubepos(x,0,n), cr |
1230 | #ifdef STANDALONE_SOLVER |
1231 | , "intersectional analysis," |
1232 | " block (%d,%d) vs column %d", |
1233 | 1+x/r, 1+y, 1+x |
1234 | #endif |
1235 | ))) { |
1236 | diff = max(diff, DIFF_INTERSECT); |
1237 | goto cont; |
1238 | } |
1239 | |
1240 | /* |
1241 | * Blockwise set elimination. |
1242 | */ |
1243 | for (x = 0; x < cr; x += r) |
1244 | for (y = 0; y < r; y++) |
ab53eb64 |
1245 | if (nsolve_set(usage, scratch, cubepos(x,y,1), r*cr, 1 |
7c568a48 |
1246 | #ifdef STANDALONE_SOLVER |
1247 | , "set elimination, block (%d,%d)", 1+x/r, 1+y |
1248 | #endif |
1249 | )) { |
1250 | diff = max(diff, DIFF_SET); |
1251 | goto cont; |
1252 | } |
1253 | |
1254 | /* |
1255 | * Row-wise set elimination. |
1256 | */ |
1257 | for (y = 0; y < cr; y++) |
ab53eb64 |
1258 | if (nsolve_set(usage, scratch, cubepos(0,y,1), cr*cr, 1 |
7c568a48 |
1259 | #ifdef STANDALONE_SOLVER |
1260 | , "set elimination, row %d", 1+YUNTRANS(y) |
1261 | #endif |
1262 | )) { |
1263 | diff = max(diff, DIFF_SET); |
1264 | goto cont; |
1265 | } |
1266 | |
1267 | /* |
1268 | * Column-wise set elimination. |
1269 | */ |
1270 | for (x = 0; x < cr; x++) |
ab53eb64 |
1271 | if (nsolve_set(usage, scratch, cubepos(x,0,1), cr, 1 |
7c568a48 |
1272 | #ifdef STANDALONE_SOLVER |
1273 | , "set elimination, column %d", 1+x |
1274 | #endif |
1275 | )) { |
1276 | diff = max(diff, DIFF_SET); |
1277 | goto cont; |
1278 | } |
1d8e8ad8 |
1279 | |
1280 | /* |
1281 | * If we reach here, we have made no deductions in this |
1282 | * iteration, so the algorithm terminates. |
1283 | */ |
1284 | break; |
1285 | } |
1286 | |
ab53eb64 |
1287 | nsolve_free_scratch(scratch); |
1288 | |
1d8e8ad8 |
1289 | sfree(usage->cube); |
1290 | sfree(usage->row); |
1291 | sfree(usage->col); |
1292 | sfree(usage->blk); |
1293 | sfree(usage); |
1294 | |
1295 | for (x = 0; x < cr; x++) |
1296 | for (y = 0; y < cr; y++) |
1297 | if (!grid[y*cr+x]) |
7c568a48 |
1298 | return DIFF_IMPOSSIBLE; |
1299 | return diff; |
1d8e8ad8 |
1300 | } |
1301 | |
1302 | /* ---------------------------------------------------------------------- |
1303 | * End of non-recursive solver code. |
1304 | */ |
1305 | |
1306 | /* |
1307 | * Check whether a grid contains a valid complete puzzle. |
1308 | */ |
1309 | static int check_valid(int c, int r, digit *grid) |
1310 | { |
1311 | int cr = c*r; |
1312 | unsigned char *used; |
1313 | int x, y, n; |
1314 | |
1315 | used = snewn(cr, unsigned char); |
1316 | |
1317 | /* |
1318 | * Check that each row contains precisely one of everything. |
1319 | */ |
1320 | for (y = 0; y < cr; y++) { |
1321 | memset(used, FALSE, cr); |
1322 | for (x = 0; x < cr; x++) |
1323 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
1324 | used[grid[y*cr+x]-1] = TRUE; |
1325 | for (n = 0; n < cr; n++) |
1326 | if (!used[n]) { |
1327 | sfree(used); |
1328 | return FALSE; |
1329 | } |
1330 | } |
1331 | |
1332 | /* |
1333 | * Check that each column contains precisely one of everything. |
1334 | */ |
1335 | for (x = 0; x < cr; x++) { |
1336 | memset(used, FALSE, cr); |
1337 | for (y = 0; y < cr; y++) |
1338 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
1339 | used[grid[y*cr+x]-1] = TRUE; |
1340 | for (n = 0; n < cr; n++) |
1341 | if (!used[n]) { |
1342 | sfree(used); |
1343 | return FALSE; |
1344 | } |
1345 | } |
1346 | |
1347 | /* |
1348 | * Check that each block contains precisely one of everything. |
1349 | */ |
1350 | for (x = 0; x < cr; x += r) { |
1351 | for (y = 0; y < cr; y += c) { |
1352 | int xx, yy; |
1353 | memset(used, FALSE, cr); |
1354 | for (xx = x; xx < x+r; xx++) |
1355 | for (yy = 0; yy < y+c; yy++) |
1356 | if (grid[yy*cr+xx] > 0 && grid[yy*cr+xx] <= cr) |
1357 | used[grid[yy*cr+xx]-1] = TRUE; |
1358 | for (n = 0; n < cr; n++) |
1359 | if (!used[n]) { |
1360 | sfree(used); |
1361 | return FALSE; |
1362 | } |
1363 | } |
1364 | } |
1365 | |
1366 | sfree(used); |
1367 | return TRUE; |
1368 | } |
1369 | |
ef57b17d |
1370 | static int symmetries(game_params *params, int x, int y, int *output, int s) |
1371 | { |
1372 | int c = params->c, r = params->r, cr = c*r; |
1373 | int i = 0; |
1374 | |
154bf9b1 |
1375 | #define ADD(x,y) (*output++ = (x), *output++ = (y), i++) |
1376 | |
1377 | ADD(x, y); |
ef57b17d |
1378 | |
1379 | switch (s) { |
1380 | case SYMM_NONE: |
1381 | break; /* just x,y is all we need */ |
ef57b17d |
1382 | case SYMM_ROT2: |
154bf9b1 |
1383 | ADD(cr - 1 - x, cr - 1 - y); |
1384 | break; |
1385 | case SYMM_ROT4: |
1386 | ADD(cr - 1 - y, x); |
1387 | ADD(y, cr - 1 - x); |
1388 | ADD(cr - 1 - x, cr - 1 - y); |
1389 | break; |
1390 | case SYMM_REF2: |
1391 | ADD(cr - 1 - x, y); |
1392 | break; |
1393 | case SYMM_REF2D: |
1394 | ADD(y, x); |
1395 | break; |
1396 | case SYMM_REF4: |
1397 | ADD(cr - 1 - x, y); |
1398 | ADD(x, cr - 1 - y); |
1399 | ADD(cr - 1 - x, cr - 1 - y); |
1400 | break; |
1401 | case SYMM_REF4D: |
1402 | ADD(y, x); |
1403 | ADD(cr - 1 - x, cr - 1 - y); |
1404 | ADD(cr - 1 - y, cr - 1 - x); |
1405 | break; |
1406 | case SYMM_REF8: |
1407 | ADD(cr - 1 - x, y); |
1408 | ADD(x, cr - 1 - y); |
1409 | ADD(cr - 1 - x, cr - 1 - y); |
1410 | ADD(y, x); |
1411 | ADD(y, cr - 1 - x); |
1412 | ADD(cr - 1 - y, x); |
1413 | ADD(cr - 1 - y, cr - 1 - x); |
1414 | break; |
ef57b17d |
1415 | } |
1416 | |
154bf9b1 |
1417 | #undef ADD |
1418 | |
ef57b17d |
1419 | return i; |
1420 | } |
1421 | |
c566778e |
1422 | static char *encode_solve_move(int cr, digit *grid) |
1423 | { |
1424 | int i, len; |
1425 | char *ret, *p, *sep; |
1426 | |
1427 | /* |
1428 | * It's surprisingly easy to work out _exactly_ how long this |
1429 | * string needs to be. To decimal-encode all the numbers from 1 |
1430 | * to n: |
1431 | * |
1432 | * - every number has a units digit; total is n. |
1433 | * - all numbers above 9 have a tens digit; total is max(n-9,0). |
1434 | * - all numbers above 99 have a hundreds digit; total is max(n-99,0). |
1435 | * - and so on. |
1436 | */ |
1437 | len = 0; |
1438 | for (i = 1; i <= cr; i *= 10) |
1439 | len += max(cr - i + 1, 0); |
1440 | len += cr; /* don't forget the commas */ |
1441 | len *= cr; /* there are cr rows of these */ |
1442 | |
1443 | /* |
1444 | * Now len is one bigger than the total size of the |
1445 | * comma-separated numbers (because we counted an |
1446 | * additional leading comma). We need to have a leading S |
1447 | * and a trailing NUL, so we're off by one in total. |
1448 | */ |
1449 | len++; |
1450 | |
1451 | ret = snewn(len, char); |
1452 | p = ret; |
1453 | *p++ = 'S'; |
1454 | sep = ""; |
1455 | for (i = 0; i < cr*cr; i++) { |
1456 | p += sprintf(p, "%s%d", sep, grid[i]); |
1457 | sep = ","; |
1458 | } |
1459 | *p++ = '\0'; |
1460 | assert(p - ret == len); |
1461 | |
1462 | return ret; |
1463 | } |
3220eba4 |
1464 | |
1185e3c5 |
1465 | static char *new_game_desc(game_params *params, random_state *rs, |
c566778e |
1466 | char **aux, int interactive) |
1d8e8ad8 |
1467 | { |
1468 | int c = params->c, r = params->r, cr = c*r; |
1469 | int area = cr*cr; |
1470 | digit *grid, *grid2; |
1471 | struct xy { int x, y; } *locs; |
1472 | int nlocs; |
1473 | int ret; |
1185e3c5 |
1474 | char *desc; |
ef57b17d |
1475 | int coords[16], ncoords; |
154bf9b1 |
1476 | int *symmclasses, nsymmclasses; |
de60d8bd |
1477 | int maxdiff, recursing; |
1d8e8ad8 |
1478 | |
1479 | /* |
7c568a48 |
1480 | * Adjust the maximum difficulty level to be consistent with |
1481 | * the puzzle size: all 2x2 puzzles appear to be Trivial |
1482 | * (DIFF_BLOCK) so we cannot hold out for even a Basic |
1483 | * (DIFF_SIMPLE) one. |
1d8e8ad8 |
1484 | */ |
7c568a48 |
1485 | maxdiff = params->diff; |
1486 | if (c == 2 && r == 2) |
1487 | maxdiff = DIFF_BLOCK; |
1d8e8ad8 |
1488 | |
7c568a48 |
1489 | grid = snewn(area, digit); |
ef57b17d |
1490 | locs = snewn(area, struct xy); |
1d8e8ad8 |
1491 | grid2 = snewn(area, digit); |
1d8e8ad8 |
1492 | |
7c568a48 |
1493 | /* |
154bf9b1 |
1494 | * Find the set of equivalence classes of squares permitted |
1495 | * by the selected symmetry. We do this by enumerating all |
1496 | * the grid squares which have no symmetric companion |
1497 | * sorting lower than themselves. |
1498 | */ |
1499 | nsymmclasses = 0; |
1500 | symmclasses = snewn(cr * cr, int); |
1501 | { |
1502 | int x, y; |
1503 | |
1504 | for (y = 0; y < cr; y++) |
1505 | for (x = 0; x < cr; x++) { |
1506 | int i = y*cr+x; |
1507 | int j; |
1508 | |
1509 | ncoords = symmetries(params, x, y, coords, params->symm); |
1510 | for (j = 0; j < ncoords; j++) |
1511 | if (coords[2*j+1]*cr+coords[2*j] < i) |
1512 | break; |
1513 | if (j == ncoords) |
1514 | symmclasses[nsymmclasses++] = i; |
1515 | } |
1516 | } |
1517 | |
1518 | /* |
7c568a48 |
1519 | * Loop until we get a grid of the required difficulty. This is |
1520 | * nasty, but it seems to be unpleasantly hard to generate |
1521 | * difficult grids otherwise. |
1522 | */ |
1523 | do { |
1524 | /* |
1525 | * Start the recursive solver with an empty grid to generate a |
1526 | * random solved state. |
1527 | */ |
1528 | memset(grid, 0, area); |
1529 | ret = rsolve(c, r, grid, rs, 1); |
1530 | assert(ret == 1); |
1531 | assert(check_valid(c, r, grid)); |
1532 | |
3220eba4 |
1533 | /* |
c566778e |
1534 | * Save the solved grid in aux. |
3220eba4 |
1535 | */ |
1536 | { |
ab53eb64 |
1537 | /* |
1538 | * We might already have written *aux the last time we |
1539 | * went round this loop, in which case we should free |
c566778e |
1540 | * the old aux before overwriting it with the new one. |
ab53eb64 |
1541 | */ |
1542 | if (*aux) { |
ab53eb64 |
1543 | sfree(*aux); |
1544 | } |
c566778e |
1545 | |
1546 | *aux = encode_solve_move(cr, grid); |
3220eba4 |
1547 | } |
1548 | |
7c568a48 |
1549 | /* |
1550 | * Now we have a solved grid, start removing things from it |
1551 | * while preserving solubility. |
1552 | */ |
de60d8bd |
1553 | recursing = FALSE; |
7c568a48 |
1554 | while (1) { |
1555 | int x, y, i, j; |
1556 | |
1557 | /* |
1558 | * Iterate over the grid and enumerate all the filled |
1559 | * squares we could empty. |
1560 | */ |
1561 | nlocs = 0; |
1562 | |
154bf9b1 |
1563 | for (i = 0; i < nsymmclasses; i++) { |
1564 | x = symmclasses[i] % cr; |
1565 | y = symmclasses[i] / cr; |
1566 | if (grid[y*cr+x]) { |
1567 | locs[nlocs].x = x; |
1568 | locs[nlocs].y = y; |
1569 | nlocs++; |
1570 | } |
1571 | } |
7c568a48 |
1572 | |
1573 | /* |
1574 | * Now shuffle that list. |
1575 | */ |
1576 | for (i = nlocs; i > 1; i--) { |
1577 | int p = random_upto(rs, i); |
1578 | if (p != i-1) { |
1579 | struct xy t = locs[p]; |
1580 | locs[p] = locs[i-1]; |
1581 | locs[i-1] = t; |
1582 | } |
1583 | } |
1584 | |
1585 | /* |
1586 | * Now loop over the shuffled list and, for each element, |
1587 | * see whether removing that element (and its reflections) |
1588 | * from the grid will still leave the grid soluble by |
1589 | * nsolve. |
1590 | */ |
1591 | for (i = 0; i < nlocs; i++) { |
de60d8bd |
1592 | int ret; |
1593 | |
7c568a48 |
1594 | x = locs[i].x; |
1595 | y = locs[i].y; |
1596 | |
1597 | memcpy(grid2, grid, area); |
1598 | ncoords = symmetries(params, x, y, coords, params->symm); |
1599 | for (j = 0; j < ncoords; j++) |
1600 | grid2[coords[2*j+1]*cr+coords[2*j]] = 0; |
1601 | |
de60d8bd |
1602 | if (recursing) |
1603 | ret = (rsolve(c, r, grid2, NULL, 2) == 1); |
1604 | else |
1605 | ret = (nsolve(c, r, grid2) <= maxdiff); |
1606 | |
1607 | if (ret) { |
7c568a48 |
1608 | for (j = 0; j < ncoords; j++) |
1609 | grid[coords[2*j+1]*cr+coords[2*j]] = 0; |
1610 | break; |
1611 | } |
1612 | } |
1613 | |
1614 | if (i == nlocs) { |
1615 | /* |
de60d8bd |
1616 | * There was nothing we could remove without |
1617 | * destroying solvability. If we're trying to |
1618 | * generate a recursion-only grid and haven't |
1619 | * switched over to rsolve yet, we now do; |
1620 | * otherwise we give up. |
7c568a48 |
1621 | */ |
de60d8bd |
1622 | if (maxdiff == DIFF_RECURSIVE && !recursing) { |
1623 | recursing = TRUE; |
1624 | } else { |
1625 | break; |
1626 | } |
7c568a48 |
1627 | } |
1628 | } |
1d8e8ad8 |
1629 | |
7c568a48 |
1630 | memcpy(grid2, grid, area); |
de60d8bd |
1631 | } while (nsolve(c, r, grid2) < maxdiff); |
1d8e8ad8 |
1632 | |
1d8e8ad8 |
1633 | sfree(grid2); |
1634 | sfree(locs); |
1635 | |
154bf9b1 |
1636 | sfree(symmclasses); |
1637 | |
1d8e8ad8 |
1638 | /* |
1639 | * Now we have the grid as it will be presented to the user. |
1185e3c5 |
1640 | * Encode it in a game desc. |
1d8e8ad8 |
1641 | */ |
1642 | { |
1643 | char *p; |
1644 | int run, i; |
1645 | |
1185e3c5 |
1646 | desc = snewn(5 * area, char); |
1647 | p = desc; |
1d8e8ad8 |
1648 | run = 0; |
1649 | for (i = 0; i <= area; i++) { |
1650 | int n = (i < area ? grid[i] : -1); |
1651 | |
1652 | if (!n) |
1653 | run++; |
1654 | else { |
1655 | if (run) { |
1656 | while (run > 0) { |
1657 | int c = 'a' - 1 + run; |
1658 | if (run > 26) |
1659 | c = 'z'; |
1660 | *p++ = c; |
1661 | run -= c - ('a' - 1); |
1662 | } |
1663 | } else { |
1664 | /* |
1665 | * If there's a number in the very top left or |
1666 | * bottom right, there's no point putting an |
1667 | * unnecessary _ before or after it. |
1668 | */ |
1185e3c5 |
1669 | if (p > desc && n > 0) |
1d8e8ad8 |
1670 | *p++ = '_'; |
1671 | } |
1672 | if (n > 0) |
1673 | p += sprintf(p, "%d", n); |
1674 | run = 0; |
1675 | } |
1676 | } |
1185e3c5 |
1677 | assert(p - desc < 5 * area); |
1d8e8ad8 |
1678 | *p++ = '\0'; |
1185e3c5 |
1679 | desc = sresize(desc, p - desc, char); |
1d8e8ad8 |
1680 | } |
1681 | |
1682 | sfree(grid); |
1683 | |
1185e3c5 |
1684 | return desc; |
1d8e8ad8 |
1685 | } |
1686 | |
1185e3c5 |
1687 | static char *validate_desc(game_params *params, char *desc) |
1d8e8ad8 |
1688 | { |
1689 | int area = params->r * params->r * params->c * params->c; |
1690 | int squares = 0; |
1691 | |
1185e3c5 |
1692 | while (*desc) { |
1693 | int n = *desc++; |
1d8e8ad8 |
1694 | if (n >= 'a' && n <= 'z') { |
1695 | squares += n - 'a' + 1; |
1696 | } else if (n == '_') { |
1697 | /* do nothing */; |
1698 | } else if (n > '0' && n <= '9') { |
1699 | squares++; |
1185e3c5 |
1700 | while (*desc >= '0' && *desc <= '9') |
1701 | desc++; |
1d8e8ad8 |
1702 | } else |
1185e3c5 |
1703 | return "Invalid character in game description"; |
1d8e8ad8 |
1704 | } |
1705 | |
1706 | if (squares < area) |
1707 | return "Not enough data to fill grid"; |
1708 | |
1709 | if (squares > area) |
1710 | return "Too much data to fit in grid"; |
1711 | |
1712 | return NULL; |
1713 | } |
1714 | |
c380832d |
1715 | static game_state *new_game(midend_data *me, game_params *params, char *desc) |
1d8e8ad8 |
1716 | { |
1717 | game_state *state = snew(game_state); |
1718 | int c = params->c, r = params->r, cr = c*r, area = cr * cr; |
1719 | int i; |
1720 | |
1721 | state->c = params->c; |
1722 | state->r = params->r; |
1723 | |
1724 | state->grid = snewn(area, digit); |
c8266e03 |
1725 | state->pencil = snewn(area * cr, unsigned char); |
1726 | memset(state->pencil, 0, area * cr); |
1d8e8ad8 |
1727 | state->immutable = snewn(area, unsigned char); |
1728 | memset(state->immutable, FALSE, area); |
1729 | |
2ac6d24e |
1730 | state->completed = state->cheated = FALSE; |
1d8e8ad8 |
1731 | |
1732 | i = 0; |
1185e3c5 |
1733 | while (*desc) { |
1734 | int n = *desc++; |
1d8e8ad8 |
1735 | if (n >= 'a' && n <= 'z') { |
1736 | int run = n - 'a' + 1; |
1737 | assert(i + run <= area); |
1738 | while (run-- > 0) |
1739 | state->grid[i++] = 0; |
1740 | } else if (n == '_') { |
1741 | /* do nothing */; |
1742 | } else if (n > '0' && n <= '9') { |
1743 | assert(i < area); |
1744 | state->immutable[i] = TRUE; |
1185e3c5 |
1745 | state->grid[i++] = atoi(desc-1); |
1746 | while (*desc >= '0' && *desc <= '9') |
1747 | desc++; |
1d8e8ad8 |
1748 | } else { |
1749 | assert(!"We can't get here"); |
1750 | } |
1751 | } |
1752 | assert(i == area); |
1753 | |
1754 | return state; |
1755 | } |
1756 | |
1757 | static game_state *dup_game(game_state *state) |
1758 | { |
1759 | game_state *ret = snew(game_state); |
1760 | int c = state->c, r = state->r, cr = c*r, area = cr * cr; |
1761 | |
1762 | ret->c = state->c; |
1763 | ret->r = state->r; |
1764 | |
1765 | ret->grid = snewn(area, digit); |
1766 | memcpy(ret->grid, state->grid, area); |
1767 | |
c8266e03 |
1768 | ret->pencil = snewn(area * cr, unsigned char); |
1769 | memcpy(ret->pencil, state->pencil, area * cr); |
1770 | |
1d8e8ad8 |
1771 | ret->immutable = snewn(area, unsigned char); |
1772 | memcpy(ret->immutable, state->immutable, area); |
1773 | |
1774 | ret->completed = state->completed; |
2ac6d24e |
1775 | ret->cheated = state->cheated; |
1d8e8ad8 |
1776 | |
1777 | return ret; |
1778 | } |
1779 | |
1780 | static void free_game(game_state *state) |
1781 | { |
1782 | sfree(state->immutable); |
c8266e03 |
1783 | sfree(state->pencil); |
1d8e8ad8 |
1784 | sfree(state->grid); |
1785 | sfree(state); |
1786 | } |
1787 | |
df11cd4e |
1788 | static char *solve_game(game_state *state, game_state *currstate, |
c566778e |
1789 | char *ai, char **error) |
2ac6d24e |
1790 | { |
3220eba4 |
1791 | int c = state->c, r = state->r, cr = c*r; |
c566778e |
1792 | char *ret; |
df11cd4e |
1793 | digit *grid; |
c566778e |
1794 | int rsolve_ret; |
2ac6d24e |
1795 | |
3220eba4 |
1796 | /* |
c566778e |
1797 | * If we already have the solution in ai, save ourselves some |
1798 | * time. |
3220eba4 |
1799 | */ |
c566778e |
1800 | if (ai) |
1801 | return dupstr(ai); |
3220eba4 |
1802 | |
c566778e |
1803 | grid = snewn(cr*cr, digit); |
1804 | memcpy(grid, state->grid, cr*cr); |
1805 | rsolve_ret = rsolve(c, r, grid, NULL, 2); |
df11cd4e |
1806 | |
c566778e |
1807 | if (rsolve_ret != 1) { |
1808 | sfree(grid); |
1809 | if (rsolve_ret == 0) |
1810 | *error = "No solution exists for this puzzle"; |
1811 | else |
1812 | *error = "Multiple solutions exist for this puzzle"; |
1813 | return NULL; |
df11cd4e |
1814 | } |
1815 | |
c566778e |
1816 | ret = encode_solve_move(cr, grid); |
df11cd4e |
1817 | |
c566778e |
1818 | sfree(grid); |
2ac6d24e |
1819 | |
1820 | return ret; |
1821 | } |
1822 | |
9b4b03d3 |
1823 | static char *grid_text_format(int c, int r, digit *grid) |
1824 | { |
1825 | int cr = c*r; |
1826 | int x, y; |
1827 | int maxlen; |
1828 | char *ret, *p; |
1829 | |
1830 | /* |
1831 | * There are cr lines of digits, plus r-1 lines of block |
1832 | * separators. Each line contains cr digits, cr-1 separating |
1833 | * spaces, and c-1 two-character block separators. Thus, the |
1834 | * total length of a line is 2*cr+2*c-3 (not counting the |
1835 | * newline), and there are cr+r-1 of them. |
1836 | */ |
1837 | maxlen = (cr+r-1) * (2*cr+2*c-2); |
1838 | ret = snewn(maxlen+1, char); |
1839 | p = ret; |
1840 | |
1841 | for (y = 0; y < cr; y++) { |
1842 | for (x = 0; x < cr; x++) { |
1843 | int ch = grid[y * cr + x]; |
1844 | if (ch == 0) |
1845 | ch = ' '; |
1846 | else if (ch <= 9) |
1847 | ch = '0' + ch; |
1848 | else |
1849 | ch = 'a' + ch-10; |
1850 | *p++ = ch; |
1851 | if (x+1 < cr) { |
1852 | *p++ = ' '; |
1853 | if ((x+1) % r == 0) { |
1854 | *p++ = '|'; |
1855 | *p++ = ' '; |
1856 | } |
1857 | } |
1858 | } |
1859 | *p++ = '\n'; |
1860 | if (y+1 < cr && (y+1) % c == 0) { |
1861 | for (x = 0; x < cr; x++) { |
1862 | *p++ = '-'; |
1863 | if (x+1 < cr) { |
1864 | *p++ = '-'; |
1865 | if ((x+1) % r == 0) { |
1866 | *p++ = '+'; |
1867 | *p++ = '-'; |
1868 | } |
1869 | } |
1870 | } |
1871 | *p++ = '\n'; |
1872 | } |
1873 | } |
1874 | |
1875 | assert(p - ret == maxlen); |
1876 | *p = '\0'; |
1877 | return ret; |
1878 | } |
1879 | |
1880 | static char *game_text_format(game_state *state) |
1881 | { |
1882 | return grid_text_format(state->c, state->r, state->grid); |
1883 | } |
1884 | |
1d8e8ad8 |
1885 | struct game_ui { |
1886 | /* |
1887 | * These are the coordinates of the currently highlighted |
1888 | * square on the grid, or -1,-1 if there isn't one. When there |
1889 | * is, pressing a valid number or letter key or Space will |
1890 | * enter that number or letter in the grid. |
1891 | */ |
1892 | int hx, hy; |
c8266e03 |
1893 | /* |
1894 | * This indicates whether the current highlight is a |
1895 | * pencil-mark one or a real one. |
1896 | */ |
1897 | int hpencil; |
1d8e8ad8 |
1898 | }; |
1899 | |
1900 | static game_ui *new_ui(game_state *state) |
1901 | { |
1902 | game_ui *ui = snew(game_ui); |
1903 | |
1904 | ui->hx = ui->hy = -1; |
c8266e03 |
1905 | ui->hpencil = 0; |
1d8e8ad8 |
1906 | |
1907 | return ui; |
1908 | } |
1909 | |
1910 | static void free_ui(game_ui *ui) |
1911 | { |
1912 | sfree(ui); |
1913 | } |
1914 | |
844f605f |
1915 | static char *encode_ui(game_ui *ui) |
ae8290c6 |
1916 | { |
1917 | return NULL; |
1918 | } |
1919 | |
844f605f |
1920 | static void decode_ui(game_ui *ui, char *encoding) |
ae8290c6 |
1921 | { |
1922 | } |
1923 | |
07dfb697 |
1924 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
1925 | game_state *newstate) |
1926 | { |
1927 | int c = newstate->c, r = newstate->r, cr = c*r; |
1928 | /* |
1929 | * We prevent pencil-mode highlighting of a filled square. So |
1930 | * if the user has just filled in a square which we had a |
1931 | * pencil-mode highlight in (by Undo, or by Redo, or by Solve), |
1932 | * then we cancel the highlight. |
1933 | */ |
1934 | if (ui->hx >= 0 && ui->hy >= 0 && ui->hpencil && |
1935 | newstate->grid[ui->hy * cr + ui->hx] != 0) { |
1936 | ui->hx = ui->hy = -1; |
1937 | } |
1938 | } |
1939 | |
1e3e152d |
1940 | struct game_drawstate { |
1941 | int started; |
1942 | int c, r, cr; |
1943 | int tilesize; |
1944 | digit *grid; |
1945 | unsigned char *pencil; |
1946 | unsigned char *hl; |
1947 | /* This is scratch space used within a single call to game_redraw. */ |
1948 | int *entered_items; |
1949 | }; |
1950 | |
df11cd4e |
1951 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
1952 | int x, int y, int button) |
1d8e8ad8 |
1953 | { |
df11cd4e |
1954 | int c = state->c, r = state->r, cr = c*r; |
1d8e8ad8 |
1955 | int tx, ty; |
df11cd4e |
1956 | char buf[80]; |
1d8e8ad8 |
1957 | |
f0ee053c |
1958 | button &= ~MOD_MASK; |
3c833d45 |
1959 | |
ae812854 |
1960 | tx = (x + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
1961 | ty = (y + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
1d8e8ad8 |
1962 | |
39d682c9 |
1963 | if (tx >= 0 && tx < cr && ty >= 0 && ty < cr) { |
1964 | if (button == LEFT_BUTTON) { |
df11cd4e |
1965 | if (state->immutable[ty*cr+tx]) { |
39d682c9 |
1966 | ui->hx = ui->hy = -1; |
1967 | } else if (tx == ui->hx && ty == ui->hy && ui->hpencil == 0) { |
1968 | ui->hx = ui->hy = -1; |
1969 | } else { |
1970 | ui->hx = tx; |
1971 | ui->hy = ty; |
1972 | ui->hpencil = 0; |
1973 | } |
df11cd4e |
1974 | return ""; /* UI activity occurred */ |
39d682c9 |
1975 | } |
1976 | if (button == RIGHT_BUTTON) { |
1977 | /* |
1978 | * Pencil-mode highlighting for non filled squares. |
1979 | */ |
df11cd4e |
1980 | if (state->grid[ty*cr+tx] == 0) { |
39d682c9 |
1981 | if (tx == ui->hx && ty == ui->hy && ui->hpencil) { |
1982 | ui->hx = ui->hy = -1; |
1983 | } else { |
1984 | ui->hpencil = 1; |
1985 | ui->hx = tx; |
1986 | ui->hy = ty; |
1987 | } |
1988 | } else { |
1989 | ui->hx = ui->hy = -1; |
1990 | } |
df11cd4e |
1991 | return ""; /* UI activity occurred */ |
39d682c9 |
1992 | } |
1d8e8ad8 |
1993 | } |
1994 | |
1995 | if (ui->hx != -1 && ui->hy != -1 && |
1996 | ((button >= '1' && button <= '9' && button - '0' <= cr) || |
1997 | (button >= 'a' && button <= 'z' && button - 'a' + 10 <= cr) || |
1998 | (button >= 'A' && button <= 'Z' && button - 'A' + 10 <= cr) || |
1999 | button == ' ')) { |
2000 | int n = button - '0'; |
2001 | if (button >= 'A' && button <= 'Z') |
2002 | n = button - 'A' + 10; |
2003 | if (button >= 'a' && button <= 'z') |
2004 | n = button - 'a' + 10; |
2005 | if (button == ' ') |
2006 | n = 0; |
2007 | |
39d682c9 |
2008 | /* |
2009 | * Can't overwrite this square. In principle this shouldn't |
2010 | * happen anyway because we should never have even been |
2011 | * able to highlight the square, but it never hurts to be |
2012 | * careful. |
2013 | */ |
df11cd4e |
2014 | if (state->immutable[ui->hy*cr+ui->hx]) |
39d682c9 |
2015 | return NULL; |
1d8e8ad8 |
2016 | |
c8266e03 |
2017 | /* |
2018 | * Can't make pencil marks in a filled square. In principle |
2019 | * this shouldn't happen anyway because we should never |
2020 | * have even been able to pencil-highlight the square, but |
2021 | * it never hurts to be careful. |
2022 | */ |
df11cd4e |
2023 | if (ui->hpencil && state->grid[ui->hy*cr+ui->hx]) |
c8266e03 |
2024 | return NULL; |
2025 | |
df11cd4e |
2026 | sprintf(buf, "%c%d,%d,%d", |
2027 | ui->hpencil && n > 0 ? 'P' : 'R', ui->hx, ui->hy, n); |
2028 | |
2029 | ui->hx = ui->hy = -1; |
2030 | |
2031 | return dupstr(buf); |
2032 | } |
2033 | |
2034 | return NULL; |
2035 | } |
2036 | |
2037 | static game_state *execute_move(game_state *from, char *move) |
2038 | { |
2039 | int c = from->c, r = from->r, cr = c*r; |
2040 | game_state *ret; |
2041 | int x, y, n; |
2042 | |
2043 | if (move[0] == 'S') { |
2044 | char *p; |
2045 | |
1d8e8ad8 |
2046 | ret = dup_game(from); |
df11cd4e |
2047 | ret->completed = ret->cheated = TRUE; |
2048 | |
2049 | p = move+1; |
2050 | for (n = 0; n < cr*cr; n++) { |
2051 | ret->grid[n] = atoi(p); |
2052 | |
2053 | if (!*p || ret->grid[n] < 1 || ret->grid[n] > cr) { |
2054 | free_game(ret); |
2055 | return NULL; |
2056 | } |
2057 | |
2058 | while (*p && isdigit((unsigned char)*p)) p++; |
2059 | if (*p == ',') p++; |
2060 | } |
2061 | |
2062 | return ret; |
2063 | } else if ((move[0] == 'P' || move[0] == 'R') && |
2064 | sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 && |
2065 | x >= 0 && x < cr && y >= 0 && y < cr && n >= 0 && n <= cr) { |
2066 | |
2067 | ret = dup_game(from); |
2068 | if (move[0] == 'P' && n > 0) { |
2069 | int index = (y*cr+x) * cr + (n-1); |
c8266e03 |
2070 | ret->pencil[index] = !ret->pencil[index]; |
2071 | } else { |
df11cd4e |
2072 | ret->grid[y*cr+x] = n; |
2073 | memset(ret->pencil + (y*cr+x)*cr, 0, cr); |
1d8e8ad8 |
2074 | |
c8266e03 |
2075 | /* |
2076 | * We've made a real change to the grid. Check to see |
2077 | * if the game has been completed. |
2078 | */ |
2079 | if (!ret->completed && check_valid(c, r, ret->grid)) { |
2080 | ret->completed = TRUE; |
2081 | } |
2082 | } |
df11cd4e |
2083 | return ret; |
2084 | } else |
2085 | return NULL; /* couldn't parse move string */ |
1d8e8ad8 |
2086 | } |
2087 | |
2088 | /* ---------------------------------------------------------------------- |
2089 | * Drawing routines. |
2090 | */ |
2091 | |
1e3e152d |
2092 | #define SIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) |
2093 | #define GETTILESIZE(cr, w) ( (w-1) / (cr+1) ) |
1d8e8ad8 |
2094 | |
1e3e152d |
2095 | static void game_size(game_params *params, game_drawstate *ds, |
2096 | int *x, int *y, int expand) |
1d8e8ad8 |
2097 | { |
2098 | int c = params->c, r = params->r, cr = c*r; |
1e3e152d |
2099 | int ts; |
2100 | |
2101 | ts = min(GETTILESIZE(cr, *x), GETTILESIZE(cr, *y)); |
2102 | if (expand) |
2103 | ds->tilesize = ts; |
2104 | else |
2105 | ds->tilesize = min(ts, PREFERRED_TILE_SIZE); |
1d8e8ad8 |
2106 | |
1e3e152d |
2107 | *x = SIZE(cr); |
2108 | *y = SIZE(cr); |
1d8e8ad8 |
2109 | } |
2110 | |
2111 | static float *game_colours(frontend *fe, game_state *state, int *ncolours) |
2112 | { |
2113 | float *ret = snewn(3 * NCOLOURS, float); |
2114 | |
2115 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
2116 | |
2117 | ret[COL_GRID * 3 + 0] = 0.0F; |
2118 | ret[COL_GRID * 3 + 1] = 0.0F; |
2119 | ret[COL_GRID * 3 + 2] = 0.0F; |
2120 | |
2121 | ret[COL_CLUE * 3 + 0] = 0.0F; |
2122 | ret[COL_CLUE * 3 + 1] = 0.0F; |
2123 | ret[COL_CLUE * 3 + 2] = 0.0F; |
2124 | |
2125 | ret[COL_USER * 3 + 0] = 0.0F; |
2126 | ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1]; |
2127 | ret[COL_USER * 3 + 2] = 0.0F; |
2128 | |
2129 | ret[COL_HIGHLIGHT * 3 + 0] = 0.85F * ret[COL_BACKGROUND * 3 + 0]; |
2130 | ret[COL_HIGHLIGHT * 3 + 1] = 0.85F * ret[COL_BACKGROUND * 3 + 1]; |
2131 | ret[COL_HIGHLIGHT * 3 + 2] = 0.85F * ret[COL_BACKGROUND * 3 + 2]; |
2132 | |
7b14a9ec |
2133 | ret[COL_ERROR * 3 + 0] = 1.0F; |
2134 | ret[COL_ERROR * 3 + 1] = 0.0F; |
2135 | ret[COL_ERROR * 3 + 2] = 0.0F; |
2136 | |
c8266e03 |
2137 | ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; |
2138 | ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; |
2139 | ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2]; |
2140 | |
1d8e8ad8 |
2141 | *ncolours = NCOLOURS; |
2142 | return ret; |
2143 | } |
2144 | |
2145 | static game_drawstate *game_new_drawstate(game_state *state) |
2146 | { |
2147 | struct game_drawstate *ds = snew(struct game_drawstate); |
2148 | int c = state->c, r = state->r, cr = c*r; |
2149 | |
2150 | ds->started = FALSE; |
2151 | ds->c = c; |
2152 | ds->r = r; |
2153 | ds->cr = cr; |
2154 | ds->grid = snewn(cr*cr, digit); |
2155 | memset(ds->grid, 0, cr*cr); |
c8266e03 |
2156 | ds->pencil = snewn(cr*cr*cr, digit); |
2157 | memset(ds->pencil, 0, cr*cr*cr); |
1d8e8ad8 |
2158 | ds->hl = snewn(cr*cr, unsigned char); |
2159 | memset(ds->hl, 0, cr*cr); |
b71dd7fc |
2160 | ds->entered_items = snewn(cr*cr, int); |
1e3e152d |
2161 | ds->tilesize = 0; /* not decided yet */ |
1d8e8ad8 |
2162 | return ds; |
2163 | } |
2164 | |
2165 | static void game_free_drawstate(game_drawstate *ds) |
2166 | { |
2167 | sfree(ds->hl); |
c8266e03 |
2168 | sfree(ds->pencil); |
1d8e8ad8 |
2169 | sfree(ds->grid); |
b71dd7fc |
2170 | sfree(ds->entered_items); |
1d8e8ad8 |
2171 | sfree(ds); |
2172 | } |
2173 | |
2174 | static void draw_number(frontend *fe, game_drawstate *ds, game_state *state, |
2175 | int x, int y, int hl) |
2176 | { |
2177 | int c = state->c, r = state->r, cr = c*r; |
2178 | int tx, ty; |
2179 | int cx, cy, cw, ch; |
2180 | char str[2]; |
2181 | |
c8266e03 |
2182 | if (ds->grid[y*cr+x] == state->grid[y*cr+x] && |
2183 | ds->hl[y*cr+x] == hl && |
2184 | !memcmp(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr)) |
1d8e8ad8 |
2185 | return; /* no change required */ |
2186 | |
2187 | tx = BORDER + x * TILE_SIZE + 2; |
2188 | ty = BORDER + y * TILE_SIZE + 2; |
2189 | |
2190 | cx = tx; |
2191 | cy = ty; |
2192 | cw = TILE_SIZE-3; |
2193 | ch = TILE_SIZE-3; |
2194 | |
2195 | if (x % r) |
2196 | cx--, cw++; |
2197 | if ((x+1) % r) |
2198 | cw++; |
2199 | if (y % c) |
2200 | cy--, ch++; |
2201 | if ((y+1) % c) |
2202 | ch++; |
2203 | |
2204 | clip(fe, cx, cy, cw, ch); |
2205 | |
c8266e03 |
2206 | /* background needs erasing */ |
7b14a9ec |
2207 | draw_rect(fe, cx, cy, cw, ch, (hl & 15) == 1 ? COL_HIGHLIGHT : COL_BACKGROUND); |
c8266e03 |
2208 | |
2209 | /* pencil-mode highlight */ |
7b14a9ec |
2210 | if ((hl & 15) == 2) { |
c8266e03 |
2211 | int coords[6]; |
2212 | coords[0] = cx; |
2213 | coords[1] = cy; |
2214 | coords[2] = cx+cw/2; |
2215 | coords[3] = cy; |
2216 | coords[4] = cx; |
2217 | coords[5] = cy+ch/2; |
2218 | draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT); |
2219 | } |
1d8e8ad8 |
2220 | |
2221 | /* new number needs drawing? */ |
2222 | if (state->grid[y*cr+x]) { |
2223 | str[1] = '\0'; |
2224 | str[0] = state->grid[y*cr+x] + '0'; |
2225 | if (str[0] > '9') |
2226 | str[0] += 'a' - ('9'+1); |
2227 | draw_text(fe, tx + TILE_SIZE/2, ty + TILE_SIZE/2, |
2228 | FONT_VARIABLE, TILE_SIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE, |
7b14a9ec |
2229 | state->immutable[y*cr+x] ? COL_CLUE : (hl & 16) ? COL_ERROR : COL_USER, str); |
c8266e03 |
2230 | } else { |
edf63745 |
2231 | int i, j, npencil; |
2232 | int pw, ph, pmax, fontsize; |
2233 | |
2234 | /* count the pencil marks required */ |
2235 | for (i = npencil = 0; i < cr; i++) |
2236 | if (state->pencil[(y*cr+x)*cr+i]) |
2237 | npencil++; |
2238 | |
2239 | /* |
2240 | * It's not sensible to arrange pencil marks in the same |
2241 | * layout as the squares within a block, because this leads |
2242 | * to the font being too small. Instead, we arrange pencil |
2243 | * marks in the nearest thing we can to a square layout, |
2244 | * and we adjust the square layout depending on the number |
2245 | * of pencil marks in the square. |
2246 | */ |
2247 | for (pw = 1; pw * pw < npencil; pw++); |
2248 | if (pw < 3) pw = 3; /* otherwise it just looks _silly_ */ |
2249 | ph = (npencil + pw - 1) / pw; |
2250 | if (ph < 2) ph = 2; /* likewise */ |
2251 | pmax = max(pw, ph); |
2252 | fontsize = TILE_SIZE/(pmax*(11-pmax)/8); |
c8266e03 |
2253 | |
2254 | for (i = j = 0; i < cr; i++) |
2255 | if (state->pencil[(y*cr+x)*cr+i]) { |
edf63745 |
2256 | int dx = j % pw, dy = j / pw; |
2257 | |
c8266e03 |
2258 | str[1] = '\0'; |
2259 | str[0] = i + '1'; |
2260 | if (str[0] > '9') |
2261 | str[0] += 'a' - ('9'+1); |
edf63745 |
2262 | draw_text(fe, tx + (4*dx+3) * TILE_SIZE / (4*pw+2), |
2263 | ty + (4*dy+3) * TILE_SIZE / (4*ph+2), |
2264 | FONT_VARIABLE, fontsize, |
c8266e03 |
2265 | ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str); |
2266 | j++; |
2267 | } |
1d8e8ad8 |
2268 | } |
2269 | |
2270 | unclip(fe); |
2271 | |
2272 | draw_update(fe, cx, cy, cw, ch); |
2273 | |
2274 | ds->grid[y*cr+x] = state->grid[y*cr+x]; |
c8266e03 |
2275 | memcpy(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr); |
1d8e8ad8 |
2276 | ds->hl[y*cr+x] = hl; |
2277 | } |
2278 | |
2279 | static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, |
2280 | game_state *state, int dir, game_ui *ui, |
2281 | float animtime, float flashtime) |
2282 | { |
2283 | int c = state->c, r = state->r, cr = c*r; |
2284 | int x, y; |
2285 | |
2286 | if (!ds->started) { |
2287 | /* |
2288 | * The initial contents of the window are not guaranteed |
2289 | * and can vary with front ends. To be on the safe side, |
2290 | * all games should start by drawing a big |
2291 | * background-colour rectangle covering the whole window. |
2292 | */ |
1e3e152d |
2293 | draw_rect(fe, 0, 0, SIZE(cr), SIZE(cr), COL_BACKGROUND); |
1d8e8ad8 |
2294 | |
2295 | /* |
2296 | * Draw the grid. |
2297 | */ |
2298 | for (x = 0; x <= cr; x++) { |
2299 | int thick = (x % r ? 0 : 1); |
2300 | draw_rect(fe, BORDER + x*TILE_SIZE - thick, BORDER-1, |
2301 | 1+2*thick, cr*TILE_SIZE+3, COL_GRID); |
2302 | } |
2303 | for (y = 0; y <= cr; y++) { |
2304 | int thick = (y % c ? 0 : 1); |
2305 | draw_rect(fe, BORDER-1, BORDER + y*TILE_SIZE - thick, |
2306 | cr*TILE_SIZE+3, 1+2*thick, COL_GRID); |
2307 | } |
2308 | } |
2309 | |
2310 | /* |
7b14a9ec |
2311 | * This array is used to keep track of rows, columns and boxes |
2312 | * which contain a number more than once. |
2313 | */ |
2314 | for (x = 0; x < cr * cr; x++) |
b71dd7fc |
2315 | ds->entered_items[x] = 0; |
7b14a9ec |
2316 | for (x = 0; x < cr; x++) |
2317 | for (y = 0; y < cr; y++) { |
2318 | digit d = state->grid[y*cr+x]; |
2319 | if (d) { |
2320 | int box = (x/r)+(y/c)*c; |
b71dd7fc |
2321 | ds->entered_items[x*cr+d-1] |= ((ds->entered_items[x*cr+d-1] & 1) << 1) | 1; |
2322 | ds->entered_items[y*cr+d-1] |= ((ds->entered_items[y*cr+d-1] & 4) << 1) | 4; |
2323 | ds->entered_items[box*cr+d-1] |= ((ds->entered_items[box*cr+d-1] & 16) << 1) | 16; |
7b14a9ec |
2324 | } |
2325 | } |
2326 | |
2327 | /* |
1d8e8ad8 |
2328 | * Draw any numbers which need redrawing. |
2329 | */ |
2330 | for (x = 0; x < cr; x++) { |
2331 | for (y = 0; y < cr; y++) { |
c8266e03 |
2332 | int highlight = 0; |
7b14a9ec |
2333 | digit d = state->grid[y*cr+x]; |
2334 | |
c8266e03 |
2335 | if (flashtime > 0 && |
2336 | (flashtime <= FLASH_TIME/3 || |
2337 | flashtime >= FLASH_TIME*2/3)) |
2338 | highlight = 1; |
7b14a9ec |
2339 | |
2340 | /* Highlight active input areas. */ |
c8266e03 |
2341 | if (x == ui->hx && y == ui->hy) |
2342 | highlight = ui->hpencil ? 2 : 1; |
7b14a9ec |
2343 | |
2344 | /* Mark obvious errors (ie, numbers which occur more than once |
2345 | * in a single row, column, or box). */ |
5d744557 |
2346 | if (d && ((ds->entered_items[x*cr+d-1] & 2) || |
2347 | (ds->entered_items[y*cr+d-1] & 8) || |
2348 | (ds->entered_items[((x/r)+(y/c)*c)*cr+d-1] & 32))) |
7b14a9ec |
2349 | highlight |= 16; |
2350 | |
c8266e03 |
2351 | draw_number(fe, ds, state, x, y, highlight); |
1d8e8ad8 |
2352 | } |
2353 | } |
2354 | |
2355 | /* |
2356 | * Update the _entire_ grid if necessary. |
2357 | */ |
2358 | if (!ds->started) { |
1e3e152d |
2359 | draw_update(fe, 0, 0, SIZE(cr), SIZE(cr)); |
1d8e8ad8 |
2360 | ds->started = TRUE; |
2361 | } |
2362 | } |
2363 | |
2364 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
e3f21163 |
2365 | int dir, game_ui *ui) |
1d8e8ad8 |
2366 | { |
2367 | return 0.0F; |
2368 | } |
2369 | |
2370 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
e3f21163 |
2371 | int dir, game_ui *ui) |
1d8e8ad8 |
2372 | { |
2ac6d24e |
2373 | if (!oldstate->completed && newstate->completed && |
2374 | !oldstate->cheated && !newstate->cheated) |
1d8e8ad8 |
2375 | return FLASH_TIME; |
2376 | return 0.0F; |
2377 | } |
2378 | |
2379 | static int game_wants_statusbar(void) |
2380 | { |
2381 | return FALSE; |
2382 | } |
2383 | |
48dcdd62 |
2384 | static int game_timing_state(game_state *state) |
2385 | { |
2386 | return TRUE; |
2387 | } |
2388 | |
1d8e8ad8 |
2389 | #ifdef COMBINED |
2390 | #define thegame solo |
2391 | #endif |
2392 | |
2393 | const struct game thegame = { |
1d228b10 |
2394 | "Solo", "games.solo", |
1d8e8ad8 |
2395 | default_params, |
2396 | game_fetch_preset, |
2397 | decode_params, |
2398 | encode_params, |
2399 | free_params, |
2400 | dup_params, |
1d228b10 |
2401 | TRUE, game_configure, custom_params, |
1d8e8ad8 |
2402 | validate_params, |
1185e3c5 |
2403 | new_game_desc, |
1185e3c5 |
2404 | validate_desc, |
1d8e8ad8 |
2405 | new_game, |
2406 | dup_game, |
2407 | free_game, |
2ac6d24e |
2408 | TRUE, solve_game, |
9b4b03d3 |
2409 | TRUE, game_text_format, |
1d8e8ad8 |
2410 | new_ui, |
2411 | free_ui, |
ae8290c6 |
2412 | encode_ui, |
2413 | decode_ui, |
07dfb697 |
2414 | game_changed_state, |
df11cd4e |
2415 | interpret_move, |
2416 | execute_move, |
1d8e8ad8 |
2417 | game_size, |
2418 | game_colours, |
2419 | game_new_drawstate, |
2420 | game_free_drawstate, |
2421 | game_redraw, |
2422 | game_anim_length, |
2423 | game_flash_length, |
2424 | game_wants_statusbar, |
48dcdd62 |
2425 | FALSE, game_timing_state, |
93b1da3d |
2426 | 0, /* mouse_priorities */ |
1d8e8ad8 |
2427 | }; |
3ddae0ff |
2428 | |
2429 | #ifdef STANDALONE_SOLVER |
2430 | |
7c568a48 |
2431 | /* |
2432 | * gcc -DSTANDALONE_SOLVER -o solosolver solo.c malloc.c |
2433 | */ |
2434 | |
3ddae0ff |
2435 | void frontend_default_colour(frontend *fe, float *output) {} |
2436 | void draw_text(frontend *fe, int x, int y, int fonttype, int fontsize, |
2437 | int align, int colour, char *text) {} |
2438 | void draw_rect(frontend *fe, int x, int y, int w, int h, int colour) {} |
2439 | void draw_line(frontend *fe, int x1, int y1, int x2, int y2, int colour) {} |
2440 | void draw_polygon(frontend *fe, int *coords, int npoints, |
2441 | int fill, int colour) {} |
2442 | void clip(frontend *fe, int x, int y, int w, int h) {} |
2443 | void unclip(frontend *fe) {} |
2444 | void start_draw(frontend *fe) {} |
2445 | void draw_update(frontend *fe, int x, int y, int w, int h) {} |
2446 | void end_draw(frontend *fe) {} |
7c568a48 |
2447 | unsigned long random_bits(random_state *state, int bits) |
2448 | { assert(!"Shouldn't get randomness"); return 0; } |
2449 | unsigned long random_upto(random_state *state, unsigned long limit) |
2450 | { assert(!"Shouldn't get randomness"); return 0; } |
3ddae0ff |
2451 | |
2452 | void fatal(char *fmt, ...) |
2453 | { |
2454 | va_list ap; |
2455 | |
2456 | fprintf(stderr, "fatal error: "); |
2457 | |
2458 | va_start(ap, fmt); |
2459 | vfprintf(stderr, fmt, ap); |
2460 | va_end(ap); |
2461 | |
2462 | fprintf(stderr, "\n"); |
2463 | exit(1); |
2464 | } |
2465 | |
2466 | int main(int argc, char **argv) |
2467 | { |
2468 | game_params *p; |
2469 | game_state *s; |
7c568a48 |
2470 | int recurse = TRUE; |
1185e3c5 |
2471 | char *id = NULL, *desc, *err; |
3ddae0ff |
2472 | int y, x; |
7c568a48 |
2473 | int grade = FALSE; |
3ddae0ff |
2474 | |
2475 | while (--argc > 0) { |
2476 | char *p = *++argv; |
2477 | if (!strcmp(p, "-r")) { |
2478 | recurse = TRUE; |
2479 | } else if (!strcmp(p, "-n")) { |
2480 | recurse = FALSE; |
7c568a48 |
2481 | } else if (!strcmp(p, "-v")) { |
2482 | solver_show_working = TRUE; |
2483 | recurse = FALSE; |
2484 | } else if (!strcmp(p, "-g")) { |
2485 | grade = TRUE; |
2486 | recurse = FALSE; |
3ddae0ff |
2487 | } else if (*p == '-') { |
2488 | fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0]); |
2489 | return 1; |
2490 | } else { |
2491 | id = p; |
2492 | } |
2493 | } |
2494 | |
2495 | if (!id) { |
7c568a48 |
2496 | fprintf(stderr, "usage: %s [-n | -r | -g | -v] <game_id>\n", argv[0]); |
3ddae0ff |
2497 | return 1; |
2498 | } |
2499 | |
1185e3c5 |
2500 | desc = strchr(id, ':'); |
2501 | if (!desc) { |
3ddae0ff |
2502 | fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); |
2503 | return 1; |
2504 | } |
1185e3c5 |
2505 | *desc++ = '\0'; |
3ddae0ff |
2506 | |
1733f4ca |
2507 | p = default_params(); |
2508 | decode_params(p, id); |
1185e3c5 |
2509 | err = validate_desc(p, desc); |
3ddae0ff |
2510 | if (err) { |
2511 | fprintf(stderr, "%s: %s\n", argv[0], err); |
2512 | return 1; |
2513 | } |
39d682c9 |
2514 | s = new_game(NULL, p, desc); |
3ddae0ff |
2515 | |
2516 | if (recurse) { |
2517 | int ret = rsolve(p->c, p->r, s->grid, NULL, 2); |
2518 | if (ret > 1) { |
7c568a48 |
2519 | fprintf(stderr, "%s: rsolve: multiple solutions detected\n", |
2520 | argv[0]); |
3ddae0ff |
2521 | } |
2522 | } else { |
7c568a48 |
2523 | int ret = nsolve(p->c, p->r, s->grid); |
2524 | if (grade) { |
2525 | if (ret == DIFF_IMPOSSIBLE) { |
2526 | /* |
2527 | * Now resort to rsolve to determine whether it's |
2528 | * really soluble. |
2529 | */ |
2530 | ret = rsolve(p->c, p->r, s->grid, NULL, 2); |
2531 | if (ret == 0) |
2532 | ret = DIFF_IMPOSSIBLE; |
2533 | else if (ret == 1) |
2534 | ret = DIFF_RECURSIVE; |
2535 | else |
2536 | ret = DIFF_AMBIGUOUS; |
2537 | } |
d5958d3f |
2538 | printf("Difficulty rating: %s\n", |
2539 | ret==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)": |
2540 | ret==DIFF_SIMPLE ? "Basic (row/column/number elimination required)": |
2541 | ret==DIFF_INTERSECT ? "Intermediate (intersectional analysis required)": |
2542 | ret==DIFF_SET ? "Advanced (set elimination required)": |
2543 | ret==DIFF_RECURSIVE ? "Unreasonable (guesswork and backtracking required)": |
2544 | ret==DIFF_AMBIGUOUS ? "Ambiguous (multiple solutions exist)": |
2545 | ret==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)": |
7c568a48 |
2546 | "INTERNAL ERROR: unrecognised difficulty code"); |
2547 | } |
3ddae0ff |
2548 | } |
2549 | |
9b4b03d3 |
2550 | printf("%s\n", grid_text_format(p->c, p->r, s->grid)); |
3ddae0ff |
2551 | |
2552 | return 0; |
2553 | } |
2554 | |
2555 | #endif |