1d8e8ad8 |
1 | /* |
2 | * solo.c: the number-placing puzzle most popularly known as `Sudoku'. |
3 | * |
4 | * TODO: |
5 | * |
fbd0fc79 |
6 | * - Jigsaw Sudoku is currently an undocumented feature enabled |
7 | * by setting r (`Rows of sub-blocks' in the GUI configurer) to |
8 | * 1. The reason it's undocumented is because they're rather |
9 | * erratic to generate, because gridgen tends to hang up for |
10 | * ages. I think this is because some jigsaw block layouts |
11 | * simply do not admit very many valid filled grids (and |
12 | * perhaps some have none at all). |
13 | * + To fix this, I think probably the solution is a change in |
14 | * grid generation policy: gridgen needs to have less of an |
15 | * all-or-nothing attitude and instead make only a limited |
16 | * amount of effort to construct a filled grid before giving |
17 | * up and trying a new layout. (Come to think of it, this |
18 | * same change might also make 5x5 standard Sudoku more |
19 | * practical to generate, if correctly tuned.) |
20 | * + If I get this fixed, other work needed on jigsaw mode is: |
21 | * * introduce a GUI config checkbox. game_configure() |
22 | * ticks this box iff r==1; if it's ticked in a call to |
23 | * custom_params(), we replace (c, r) with (c*r, 1). |
24 | * * document it. |
25 | * |
c8266e03 |
26 | * - reports from users are that `Trivial'-mode puzzles are still |
27 | * rather hard compared to newspapers' easy ones, so some better |
28 | * low-end difficulty grading would be nice |
29 | * + it's possible that really easy puzzles always have |
30 | * _several_ things you can do, so don't make you hunt too |
31 | * hard for the one deduction you can currently make |
32 | * + it's also possible that easy puzzles require fewer |
33 | * cross-eliminations: perhaps there's a higher incidence of |
34 | * things you can deduce by looking only at (say) rows, |
35 | * rather than things you have to check both rows and columns |
36 | * for |
37 | * + but really, what I need to do is find some really easy |
38 | * puzzles and _play_ them, to see what's actually easy about |
39 | * them |
40 | * + while I'm revamping this area, filling in the _last_ |
41 | * number in a nearly-full row or column should certainly be |
42 | * permitted even at the lowest difficulty level. |
43 | * + also Owen noticed that `Basic' grids requiring numeric |
44 | * elimination are actually very hard, so I wonder if a |
45 | * difficulty gradation between that and positional- |
46 | * elimination-only might be in order |
47 | * + but it's not good to have _too_ many difficulty levels, or |
48 | * it'll take too long to randomly generate a given level. |
49 | * |
ef57b17d |
50 | * - it might still be nice to do some prioritisation on the |
51 | * removal of numbers from the grid |
52 | * + one possibility is to try to minimise the maximum number |
53 | * of filled squares in any block, which in particular ought |
54 | * to enforce never leaving a completely filled block in the |
55 | * puzzle as presented. |
1d8e8ad8 |
56 | * |
57 | * - alternative interface modes |
58 | * + sudoku.com's Windows program has a palette of possible |
59 | * entries; you select a palette entry first and then click |
60 | * on the square you want it to go in, thus enabling |
61 | * mouse-only play. Useful for PDAs! I don't think it's |
62 | * actually incompatible with the current highlight-then-type |
63 | * approach: you _either_ highlight a palette entry and then |
64 | * click, _or_ you highlight a square and then type. At most |
65 | * one thing is ever highlighted at a time, so there's no way |
66 | * to confuse the two. |
c8266e03 |
67 | * + then again, I don't actually like sudoku.com's interface; |
68 | * it's too much like a paint package whereas I prefer to |
69 | * think of Solo as a text editor. |
70 | * + another PDA-friendly possibility is a drag interface: |
71 | * _drag_ numbers from the palette into the grid squares. |
72 | * Thought experiments suggest I'd prefer that to the |
73 | * sudoku.com approach, but I haven't actually tried it. |
1d8e8ad8 |
74 | */ |
75 | |
76 | /* |
77 | * Solo puzzles need to be square overall (since each row and each |
78 | * column must contain one of every digit), but they need not be |
79 | * subdivided the same way internally. I am going to adopt a |
80 | * convention whereby I _always_ refer to `r' as the number of rows |
81 | * of _big_ divisions, and `c' as the number of columns of _big_ |
82 | * divisions. Thus, a 2c by 3r puzzle looks something like this: |
83 | * |
84 | * 4 5 1 | 2 6 3 |
85 | * 6 3 2 | 5 4 1 |
86 | * ------+------ (Of course, you can't subdivide it the other way |
87 | * 1 4 5 | 6 3 2 or you'll get clashes; observe that the 4 in the |
88 | * 3 2 6 | 4 1 5 top left would conflict with the 4 in the second |
89 | * ------+------ box down on the left-hand side.) |
90 | * 5 1 4 | 3 2 6 |
91 | * 2 6 3 | 1 5 4 |
92 | * |
93 | * The need for a strong naming convention should now be clear: |
94 | * each small box is two rows of digits by three columns, while the |
95 | * overall puzzle has three rows of small boxes by two columns. So |
96 | * I will (hopefully) consistently use `r' to denote the number of |
97 | * rows _of small boxes_ (here 3), which is also the number of |
98 | * columns of digits in each small box; and `c' vice versa (here |
99 | * 2). |
100 | * |
101 | * I'm also going to choose arbitrarily to list c first wherever |
102 | * possible: the above is a 2x3 puzzle, not a 3x2 one. |
103 | */ |
104 | |
105 | #include <stdio.h> |
106 | #include <stdlib.h> |
107 | #include <string.h> |
108 | #include <assert.h> |
109 | #include <ctype.h> |
110 | #include <math.h> |
111 | |
7c568a48 |
112 | #ifdef STANDALONE_SOLVER |
113 | #include <stdarg.h> |
ab362080 |
114 | int solver_show_working, solver_recurse_depth; |
7c568a48 |
115 | #endif |
116 | |
1d8e8ad8 |
117 | #include "puzzles.h" |
118 | |
119 | /* |
120 | * To save space, I store digits internally as unsigned char. This |
121 | * imposes a hard limit of 255 on the order of the puzzle. Since |
122 | * even a 5x5 takes unacceptably long to generate, I don't see this |
123 | * as a serious limitation unless something _really_ impressive |
124 | * happens in computing technology; but here's a typedef anyway for |
125 | * general good practice. |
126 | */ |
127 | typedef unsigned char digit; |
128 | #define ORDER_MAX 255 |
129 | |
1e3e152d |
130 | #define PREFERRED_TILE_SIZE 32 |
131 | #define TILE_SIZE (ds->tilesize) |
132 | #define BORDER (TILE_SIZE / 2) |
fbd0fc79 |
133 | #define GRIDEXTRA (TILE_SIZE / 32) |
1d8e8ad8 |
134 | |
135 | #define FLASH_TIME 0.4F |
136 | |
154bf9b1 |
137 | enum { SYMM_NONE, SYMM_ROT2, SYMM_ROT4, SYMM_REF2, SYMM_REF2D, SYMM_REF4, |
138 | SYMM_REF4D, SYMM_REF8 }; |
ef57b17d |
139 | |
44bf5f6f |
140 | enum { DIFF_BLOCK, DIFF_SIMPLE, DIFF_INTERSECT, DIFF_SET, DIFF_EXTREME, |
13c4d60d |
141 | DIFF_RECURSIVE, DIFF_AMBIGUOUS, DIFF_IMPOSSIBLE }; |
7c568a48 |
142 | |
1d8e8ad8 |
143 | enum { |
144 | COL_BACKGROUND, |
fbd0fc79 |
145 | COL_XDIAGONALS, |
ef57b17d |
146 | COL_GRID, |
147 | COL_CLUE, |
148 | COL_USER, |
149 | COL_HIGHLIGHT, |
7b14a9ec |
150 | COL_ERROR, |
c8266e03 |
151 | COL_PENCIL, |
ef57b17d |
152 | NCOLOURS |
1d8e8ad8 |
153 | }; |
154 | |
155 | struct game_params { |
fbd0fc79 |
156 | /* |
157 | * For a square puzzle, `c' and `r' indicate the puzzle |
158 | * parameters as described above. |
159 | * |
160 | * A jigsaw-style puzzle is indicated by r==1, in which case c |
161 | * can be whatever it likes (there is no constraint on |
162 | * compositeness - a 7x7 jigsaw sudoku makes perfect sense). |
163 | */ |
7c568a48 |
164 | int c, r, symm, diff; |
fbd0fc79 |
165 | int xtype; /* require all digits in X-diagonals */ |
1d8e8ad8 |
166 | }; |
167 | |
fbd0fc79 |
168 | struct block_structure { |
169 | int refcount; |
170 | |
171 | /* |
172 | * For text formatting, we do need c and r here. |
173 | */ |
1d8e8ad8 |
174 | int c, r; |
fbd0fc79 |
175 | |
176 | /* |
177 | * For any square index, whichblock[i] gives its block index. |
178 | * |
179 | * For 0 <= b,i < cr, blocks[b][i] gives the index of the ith |
180 | * square in block b. |
181 | * |
182 | * whichblock and blocks are each dynamically allocated in |
183 | * their own right, but the subarrays in blocks are appended |
184 | * to the whichblock array, so shouldn't be freed |
185 | * individually. |
186 | */ |
187 | int *whichblock, **blocks; |
188 | |
189 | #ifdef STANDALONE_SOLVER |
190 | /* |
191 | * Textual descriptions of each block. For normal Sudoku these |
192 | * are of the form "(1,3)"; for jigsaw they are "starting at |
193 | * (5,7)". So the sensible usage in both cases is to say |
194 | * "elimination within block %s" with one of these strings. |
195 | * |
196 | * Only blocknames itself needs individually freeing; it's all |
197 | * one block. |
198 | */ |
199 | char **blocknames; |
200 | #endif |
201 | }; |
202 | |
203 | struct game_state { |
204 | /* |
205 | * For historical reasons, I use `cr' to denote the overall |
206 | * width/height of the puzzle. It was a natural notation when |
207 | * all puzzles were divided into blocks in a grid, but doesn't |
208 | * really make much sense given jigsaw puzzles. However, the |
209 | * obvious `n' is heavily used in the solver to describe the |
210 | * index of a number being placed, so `cr' will have to stay. |
211 | */ |
212 | int cr; |
213 | struct block_structure *blocks; |
214 | int xtype; |
1d8e8ad8 |
215 | digit *grid; |
c8266e03 |
216 | unsigned char *pencil; /* c*r*c*r elements */ |
1d8e8ad8 |
217 | unsigned char *immutable; /* marks which digits are clues */ |
2ac6d24e |
218 | int completed, cheated; |
1d8e8ad8 |
219 | }; |
220 | |
221 | static game_params *default_params(void) |
222 | { |
223 | game_params *ret = snew(game_params); |
224 | |
225 | ret->c = ret->r = 3; |
fbd0fc79 |
226 | ret->xtype = FALSE; |
ef57b17d |
227 | ret->symm = SYMM_ROT2; /* a plausible default */ |
4f36adaa |
228 | ret->diff = DIFF_BLOCK; /* so is this */ |
1d8e8ad8 |
229 | |
230 | return ret; |
231 | } |
232 | |
1d8e8ad8 |
233 | static void free_params(game_params *params) |
234 | { |
235 | sfree(params); |
236 | } |
237 | |
238 | static game_params *dup_params(game_params *params) |
239 | { |
240 | game_params *ret = snew(game_params); |
241 | *ret = *params; /* structure copy */ |
242 | return ret; |
243 | } |
244 | |
7c568a48 |
245 | static int game_fetch_preset(int i, char **name, game_params **params) |
246 | { |
247 | static struct { |
248 | char *title; |
249 | game_params params; |
250 | } presets[] = { |
fbd0fc79 |
251 | { "2x2 Trivial", { 2, 2, SYMM_ROT2, DIFF_BLOCK, FALSE } }, |
252 | { "2x3 Basic", { 2, 3, SYMM_ROT2, DIFF_SIMPLE, FALSE } }, |
253 | { "3x3 Trivial", { 3, 3, SYMM_ROT2, DIFF_BLOCK, FALSE } }, |
254 | { "3x3 Basic", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, FALSE } }, |
255 | { "3x3 Basic X", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, TRUE } }, |
256 | { "3x3 Intermediate", { 3, 3, SYMM_ROT2, DIFF_INTERSECT, FALSE } }, |
257 | { "3x3 Advanced", { 3, 3, SYMM_ROT2, DIFF_SET, FALSE } }, |
258 | { "3x3 Advanced X", { 3, 3, SYMM_ROT2, DIFF_SET, TRUE } }, |
259 | { "3x3 Extreme", { 3, 3, SYMM_ROT2, DIFF_EXTREME, FALSE } }, |
260 | { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE, FALSE } }, |
ab53eb64 |
261 | #ifndef SLOW_SYSTEM |
fbd0fc79 |
262 | { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE, FALSE } }, |
263 | { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE, FALSE } }, |
ab53eb64 |
264 | #endif |
7c568a48 |
265 | }; |
266 | |
267 | if (i < 0 || i >= lenof(presets)) |
268 | return FALSE; |
269 | |
270 | *name = dupstr(presets[i].title); |
271 | *params = dup_params(&presets[i].params); |
272 | |
273 | return TRUE; |
274 | } |
275 | |
1185e3c5 |
276 | static void decode_params(game_params *ret, char const *string) |
1d8e8ad8 |
277 | { |
fbd0fc79 |
278 | int seen_r = FALSE; |
279 | |
1d8e8ad8 |
280 | ret->c = ret->r = atoi(string); |
fbd0fc79 |
281 | ret->xtype = FALSE; |
1d8e8ad8 |
282 | while (*string && isdigit((unsigned char)*string)) string++; |
283 | if (*string == 'x') { |
284 | string++; |
285 | ret->r = atoi(string); |
fbd0fc79 |
286 | seen_r = TRUE; |
1d8e8ad8 |
287 | while (*string && isdigit((unsigned char)*string)) string++; |
288 | } |
7c568a48 |
289 | while (*string) { |
fbd0fc79 |
290 | if (*string == 'j') { |
291 | string++; |
292 | if (seen_r) |
293 | ret->c *= ret->r; |
294 | ret->r = 1; |
295 | } else if (*string == 'x') { |
296 | string++; |
297 | ret->xtype = TRUE; |
298 | } else if (*string == 'r' || *string == 'm' || *string == 'a') { |
154bf9b1 |
299 | int sn, sc, sd; |
7c568a48 |
300 | sc = *string++; |
28814d46 |
301 | if (sc == 'm' && *string == 'd') { |
154bf9b1 |
302 | sd = TRUE; |
303 | string++; |
304 | } else { |
305 | sd = FALSE; |
306 | } |
7c568a48 |
307 | sn = atoi(string); |
308 | while (*string && isdigit((unsigned char)*string)) string++; |
154bf9b1 |
309 | if (sc == 'm' && sn == 8) |
310 | ret->symm = SYMM_REF8; |
7c568a48 |
311 | if (sc == 'm' && sn == 4) |
154bf9b1 |
312 | ret->symm = sd ? SYMM_REF4D : SYMM_REF4; |
313 | if (sc == 'm' && sn == 2) |
314 | ret->symm = sd ? SYMM_REF2D : SYMM_REF2; |
7c568a48 |
315 | if (sc == 'r' && sn == 4) |
316 | ret->symm = SYMM_ROT4; |
317 | if (sc == 'r' && sn == 2) |
318 | ret->symm = SYMM_ROT2; |
319 | if (sc == 'a') |
320 | ret->symm = SYMM_NONE; |
321 | } else if (*string == 'd') { |
322 | string++; |
323 | if (*string == 't') /* trivial */ |
324 | string++, ret->diff = DIFF_BLOCK; |
325 | else if (*string == 'b') /* basic */ |
326 | string++, ret->diff = DIFF_SIMPLE; |
327 | else if (*string == 'i') /* intermediate */ |
328 | string++, ret->diff = DIFF_INTERSECT; |
329 | else if (*string == 'a') /* advanced */ |
330 | string++, ret->diff = DIFF_SET; |
13c4d60d |
331 | else if (*string == 'e') /* extreme */ |
44bf5f6f |
332 | string++, ret->diff = DIFF_EXTREME; |
de60d8bd |
333 | else if (*string == 'u') /* unreasonable */ |
334 | string++, ret->diff = DIFF_RECURSIVE; |
7c568a48 |
335 | } else |
336 | string++; /* eat unknown character */ |
ef57b17d |
337 | } |
1d8e8ad8 |
338 | } |
339 | |
1185e3c5 |
340 | static char *encode_params(game_params *params, int full) |
1d8e8ad8 |
341 | { |
342 | char str[80]; |
343 | |
fbd0fc79 |
344 | if (params->r > 1) |
345 | sprintf(str, "%dx%d", params->c, params->r); |
346 | else |
347 | sprintf(str, "%dj", params->c); |
348 | if (params->xtype) |
349 | strcat(str, "x"); |
350 | |
1185e3c5 |
351 | if (full) { |
352 | switch (params->symm) { |
154bf9b1 |
353 | case SYMM_REF8: strcat(str, "m8"); break; |
1185e3c5 |
354 | case SYMM_REF4: strcat(str, "m4"); break; |
154bf9b1 |
355 | case SYMM_REF4D: strcat(str, "md4"); break; |
356 | case SYMM_REF2: strcat(str, "m2"); break; |
357 | case SYMM_REF2D: strcat(str, "md2"); break; |
1185e3c5 |
358 | case SYMM_ROT4: strcat(str, "r4"); break; |
359 | /* case SYMM_ROT2: strcat(str, "r2"); break; [default] */ |
360 | case SYMM_NONE: strcat(str, "a"); break; |
361 | } |
362 | switch (params->diff) { |
363 | /* case DIFF_BLOCK: strcat(str, "dt"); break; [default] */ |
364 | case DIFF_SIMPLE: strcat(str, "db"); break; |
365 | case DIFF_INTERSECT: strcat(str, "di"); break; |
366 | case DIFF_SET: strcat(str, "da"); break; |
44bf5f6f |
367 | case DIFF_EXTREME: strcat(str, "de"); break; |
1185e3c5 |
368 | case DIFF_RECURSIVE: strcat(str, "du"); break; |
369 | } |
370 | } |
1d8e8ad8 |
371 | return dupstr(str); |
372 | } |
373 | |
374 | static config_item *game_configure(game_params *params) |
375 | { |
376 | config_item *ret; |
377 | char buf[80]; |
378 | |
fbd0fc79 |
379 | ret = snewn(6, config_item); |
1d8e8ad8 |
380 | |
381 | ret[0].name = "Columns of sub-blocks"; |
382 | ret[0].type = C_STRING; |
383 | sprintf(buf, "%d", params->c); |
384 | ret[0].sval = dupstr(buf); |
385 | ret[0].ival = 0; |
386 | |
387 | ret[1].name = "Rows of sub-blocks"; |
388 | ret[1].type = C_STRING; |
389 | sprintf(buf, "%d", params->r); |
390 | ret[1].sval = dupstr(buf); |
391 | ret[1].ival = 0; |
392 | |
fbd0fc79 |
393 | ret[2].name = "\"X\" (require every number in each main diagonal)"; |
394 | ret[2].type = C_BOOLEAN; |
395 | ret[2].sval = NULL; |
396 | ret[2].ival = params->xtype; |
397 | |
398 | ret[3].name = "Symmetry"; |
399 | ret[3].type = C_CHOICES; |
400 | ret[3].sval = ":None:2-way rotation:4-way rotation:2-way mirror:" |
154bf9b1 |
401 | "2-way diagonal mirror:4-way mirror:4-way diagonal mirror:" |
402 | "8-way mirror"; |
fbd0fc79 |
403 | ret[3].ival = params->symm; |
ef57b17d |
404 | |
fbd0fc79 |
405 | ret[4].name = "Difficulty"; |
406 | ret[4].type = C_CHOICES; |
407 | ret[4].sval = ":Trivial:Basic:Intermediate:Advanced:Extreme:Unreasonable"; |
408 | ret[4].ival = params->diff; |
1d8e8ad8 |
409 | |
fbd0fc79 |
410 | ret[5].name = NULL; |
411 | ret[5].type = C_END; |
412 | ret[5].sval = NULL; |
413 | ret[5].ival = 0; |
1d8e8ad8 |
414 | |
415 | return ret; |
416 | } |
417 | |
418 | static game_params *custom_params(config_item *cfg) |
419 | { |
420 | game_params *ret = snew(game_params); |
421 | |
c1f743c8 |
422 | ret->c = atoi(cfg[0].sval); |
423 | ret->r = atoi(cfg[1].sval); |
fbd0fc79 |
424 | ret->xtype = cfg[2].ival; |
425 | ret->symm = cfg[3].ival; |
426 | ret->diff = cfg[4].ival; |
1d8e8ad8 |
427 | |
428 | return ret; |
429 | } |
430 | |
3ff276f2 |
431 | static char *validate_params(game_params *params, int full) |
1d8e8ad8 |
432 | { |
fbd0fc79 |
433 | if (params->c < 2) |
1d8e8ad8 |
434 | return "Both dimensions must be at least 2"; |
435 | if (params->c > ORDER_MAX || params->r > ORDER_MAX) |
436 | return "Dimensions greater than "STR(ORDER_MAX)" are not supported"; |
498eab1d |
437 | if ((params->c * params->r) > 35) |
438 | return "Unable to support more than 35 distinct symbols in a puzzle"; |
1d8e8ad8 |
439 | return NULL; |
440 | } |
441 | |
442 | /* ---------------------------------------------------------------------- |
ab362080 |
443 | * Solver. |
444 | * |
13c4d60d |
445 | * This solver is used for two purposes: |
ab362080 |
446 | * + to check solubility of a grid as we gradually remove numbers |
447 | * from it |
448 | * + to solve an externally generated puzzle when the user selects |
449 | * `Solve'. |
450 | * |
1d8e8ad8 |
451 | * It supports a variety of specific modes of reasoning. By |
452 | * enabling or disabling subsets of these modes we can arrange a |
453 | * range of difficulty levels. |
454 | */ |
455 | |
456 | /* |
457 | * Modes of reasoning currently supported: |
458 | * |
459 | * - Positional elimination: a number must go in a particular |
460 | * square because all the other empty squares in a given |
461 | * row/col/blk are ruled out. |
462 | * |
463 | * - Numeric elimination: a square must have a particular number |
464 | * in because all the other numbers that could go in it are |
465 | * ruled out. |
466 | * |
7c568a48 |
467 | * - Intersectional analysis: given two domains which overlap |
1d8e8ad8 |
468 | * (hence one must be a block, and the other can be a row or |
469 | * col), if the possible locations for a particular number in |
470 | * one of the domains can be narrowed down to the overlap, then |
471 | * that number can be ruled out everywhere but the overlap in |
472 | * the other domain too. |
473 | * |
7c568a48 |
474 | * - Set elimination: if there is a subset of the empty squares |
475 | * within a domain such that the union of the possible numbers |
476 | * in that subset has the same size as the subset itself, then |
477 | * those numbers can be ruled out everywhere else in the domain. |
478 | * (For example, if there are five empty squares and the |
479 | * possible numbers in each are 12, 23, 13, 134 and 1345, then |
480 | * the first three empty squares form such a subset: the numbers |
481 | * 1, 2 and 3 _must_ be in those three squares in some |
482 | * permutation, and hence we can deduce none of them can be in |
483 | * the fourth or fifth squares.) |
484 | * + You can also see this the other way round, concentrating |
485 | * on numbers rather than squares: if there is a subset of |
486 | * the unplaced numbers within a domain such that the union |
487 | * of all their possible positions has the same size as the |
488 | * subset itself, then all other numbers can be ruled out for |
489 | * those positions. However, it turns out that this is |
490 | * exactly equivalent to the first formulation at all times: |
491 | * there is a 1-1 correspondence between suitable subsets of |
492 | * the unplaced numbers and suitable subsets of the unfilled |
493 | * places, found by taking the _complement_ of the union of |
494 | * the numbers' possible positions (or the spaces' possible |
495 | * contents). |
ab362080 |
496 | * |
fbd0fc79 |
497 | * - Forcing chains (see comment for solver_forcing().) |
13c4d60d |
498 | * |
ab362080 |
499 | * - Recursion. If all else fails, we pick one of the currently |
500 | * most constrained empty squares and take a random guess at its |
501 | * contents, then continue solving on that basis and see if we |
502 | * get any further. |
1d8e8ad8 |
503 | */ |
504 | |
ab362080 |
505 | struct solver_usage { |
fbd0fc79 |
506 | int cr; |
507 | struct block_structure *blocks; |
1d8e8ad8 |
508 | /* |
509 | * We set up a cubic array, indexed by x, y and digit; each |
510 | * element of this array is TRUE or FALSE according to whether |
511 | * or not that digit _could_ in principle go in that position. |
512 | * |
fbd0fc79 |
513 | * The way to index this array is cube[(y*cr+x)*cr+n-1]; there |
514 | * are macros below to help with this. |
1d8e8ad8 |
515 | */ |
516 | unsigned char *cube; |
517 | /* |
518 | * This is the grid in which we write down our final |
4846f788 |
519 | * deductions. y-coordinates in here are _not_ transformed. |
1d8e8ad8 |
520 | */ |
521 | digit *grid; |
522 | /* |
523 | * Now we keep track, at a slightly higher level, of what we |
524 | * have yet to work out, to prevent doing the same deduction |
525 | * many times. |
526 | */ |
527 | /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ |
528 | unsigned char *row; |
529 | /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ |
530 | unsigned char *col; |
fbd0fc79 |
531 | /* blk[i*cr+n-1] TRUE if digit n has been placed in block i */ |
1d8e8ad8 |
532 | unsigned char *blk; |
fbd0fc79 |
533 | /* diag[i*cr+n-1] TRUE if digit n has been placed in diagonal i */ |
534 | unsigned char *diag; /* diag 0 is \, 1 is / */ |
1d8e8ad8 |
535 | }; |
fbd0fc79 |
536 | #define cubepos2(xy,n) ((xy)*usage->cr+(n)-1) |
537 | #define cubepos(x,y,n) cubepos2((y)*usage->cr+(x),n) |
4846f788 |
538 | #define cube(x,y,n) (usage->cube[cubepos(x,y,n)]) |
fbd0fc79 |
539 | #define cube2(xy,n) (usage->cube[cubepos2(xy,n)]) |
540 | |
541 | #define ondiag0(xy) ((xy) % (cr+1) == 0) |
542 | #define ondiag1(xy) ((xy) % (cr-1) == 0 && (xy) > 0 && (xy) < cr*cr-1) |
543 | #define diag0(i) ((i) * (cr+1)) |
544 | #define diag1(i) ((i+1) * (cr-1)) |
1d8e8ad8 |
545 | |
546 | /* |
547 | * Function called when we are certain that a particular square has |
4846f788 |
548 | * a particular number in it. The y-coordinate passed in here is |
549 | * transformed. |
1d8e8ad8 |
550 | */ |
ab362080 |
551 | static void solver_place(struct solver_usage *usage, int x, int y, int n) |
1d8e8ad8 |
552 | { |
fbd0fc79 |
553 | int cr = usage->cr; |
554 | int sqindex = y*cr+x; |
555 | int i, bi; |
1d8e8ad8 |
556 | |
557 | assert(cube(x,y,n)); |
558 | |
559 | /* |
560 | * Rule out all other numbers in this square. |
561 | */ |
562 | for (i = 1; i <= cr; i++) |
563 | if (i != n) |
564 | cube(x,y,i) = FALSE; |
565 | |
566 | /* |
567 | * Rule out this number in all other positions in the row. |
568 | */ |
569 | for (i = 0; i < cr; i++) |
570 | if (i != y) |
571 | cube(x,i,n) = FALSE; |
572 | |
573 | /* |
574 | * Rule out this number in all other positions in the column. |
575 | */ |
576 | for (i = 0; i < cr; i++) |
577 | if (i != x) |
578 | cube(i,y,n) = FALSE; |
579 | |
580 | /* |
581 | * Rule out this number in all other positions in the block. |
582 | */ |
fbd0fc79 |
583 | bi = usage->blocks->whichblock[sqindex]; |
584 | for (i = 0; i < cr; i++) { |
585 | int bp = usage->blocks->blocks[bi][i]; |
586 | if (bp != sqindex) |
587 | cube2(bp,n) = FALSE; |
588 | } |
1d8e8ad8 |
589 | |
590 | /* |
591 | * Enter the number in the result grid. |
592 | */ |
fbd0fc79 |
593 | usage->grid[sqindex] = n; |
1d8e8ad8 |
594 | |
595 | /* |
596 | * Cross out this number from the list of numbers left to place |
597 | * in its row, its column and its block. |
598 | */ |
599 | usage->row[y*cr+n-1] = usage->col[x*cr+n-1] = |
fbd0fc79 |
600 | usage->blk[bi*cr+n-1] = TRUE; |
601 | |
602 | if (usage->diag) { |
603 | if (ondiag0(sqindex)) { |
604 | for (i = 0; i < cr; i++) |
605 | if (diag0(i) != sqindex) |
606 | cube2(diag0(i),n) = FALSE; |
607 | usage->diag[n-1] = TRUE; |
608 | } |
609 | if (ondiag1(sqindex)) { |
610 | for (i = 0; i < cr; i++) |
611 | if (diag1(i) != sqindex) |
612 | cube2(diag1(i),n) = FALSE; |
613 | usage->diag[cr+n-1] = TRUE; |
614 | } |
615 | } |
1d8e8ad8 |
616 | } |
617 | |
fbd0fc79 |
618 | static int solver_elim(struct solver_usage *usage, int *indices |
7c568a48 |
619 | #ifdef STANDALONE_SOLVER |
620 | , char *fmt, ... |
621 | #endif |
622 | ) |
1d8e8ad8 |
623 | { |
fbd0fc79 |
624 | int cr = usage->cr; |
4846f788 |
625 | int fpos, m, i; |
1d8e8ad8 |
626 | |
627 | /* |
4846f788 |
628 | * Count the number of set bits within this section of the |
629 | * cube. |
1d8e8ad8 |
630 | */ |
631 | m = 0; |
4846f788 |
632 | fpos = -1; |
633 | for (i = 0; i < cr; i++) |
fbd0fc79 |
634 | if (usage->cube[indices[i]]) { |
635 | fpos = indices[i]; |
1d8e8ad8 |
636 | m++; |
637 | } |
638 | |
639 | if (m == 1) { |
4846f788 |
640 | int x, y, n; |
641 | assert(fpos >= 0); |
1d8e8ad8 |
642 | |
4846f788 |
643 | n = 1 + fpos % cr; |
fbd0fc79 |
644 | x = fpos / cr; |
645 | y = x / cr; |
646 | x %= cr; |
1d8e8ad8 |
647 | |
fbd0fc79 |
648 | if (!usage->grid[y*cr+x]) { |
7c568a48 |
649 | #ifdef STANDALONE_SOLVER |
650 | if (solver_show_working) { |
651 | va_list ap; |
fdb3b29a |
652 | printf("%*s", solver_recurse_depth*4, ""); |
7c568a48 |
653 | va_start(ap, fmt); |
654 | vprintf(fmt, ap); |
655 | va_end(ap); |
ab362080 |
656 | printf(":\n%*s placing %d at (%d,%d)\n", |
fbd0fc79 |
657 | solver_recurse_depth*4, "", n, 1+x, 1+y); |
7c568a48 |
658 | } |
659 | #endif |
ab362080 |
660 | solver_place(usage, x, y, n); |
661 | return +1; |
3ddae0ff |
662 | } |
ab362080 |
663 | } else if (m == 0) { |
664 | #ifdef STANDALONE_SOLVER |
665 | if (solver_show_working) { |
ab362080 |
666 | va_list ap; |
fdb3b29a |
667 | printf("%*s", solver_recurse_depth*4, ""); |
ab362080 |
668 | va_start(ap, fmt); |
669 | vprintf(fmt, ap); |
670 | va_end(ap); |
671 | printf(":\n%*s no possibilities available\n", |
672 | solver_recurse_depth*4, ""); |
673 | } |
674 | #endif |
675 | return -1; |
1d8e8ad8 |
676 | } |
677 | |
ab362080 |
678 | return 0; |
1d8e8ad8 |
679 | } |
680 | |
ab362080 |
681 | static int solver_intersect(struct solver_usage *usage, |
fbd0fc79 |
682 | int *indices1, int *indices2 |
7c568a48 |
683 | #ifdef STANDALONE_SOLVER |
684 | , char *fmt, ... |
685 | #endif |
686 | ) |
687 | { |
fbd0fc79 |
688 | int cr = usage->cr; |
689 | int ret, i, j; |
7c568a48 |
690 | |
691 | /* |
692 | * Loop over the first domain and see if there's any set bit |
693 | * not also in the second. |
694 | */ |
fbd0fc79 |
695 | for (i = j = 0; i < cr; i++) { |
696 | int p = indices1[i]; |
697 | while (j < cr && indices2[j] < p) |
698 | j++; |
699 | if (usage->cube[p]) { |
700 | if (j < cr && indices2[j] == p) |
701 | continue; /* both domains contain this index */ |
702 | else |
703 | return 0; /* there is, so we can't deduce */ |
704 | } |
7c568a48 |
705 | } |
706 | |
707 | /* |
708 | * We have determined that all set bits in the first domain are |
709 | * within its overlap with the second. So loop over the second |
710 | * domain and remove all set bits that aren't also in that |
ab362080 |
711 | * overlap; return +1 iff we actually _did_ anything. |
7c568a48 |
712 | */ |
ab362080 |
713 | ret = 0; |
fbd0fc79 |
714 | for (i = j = 0; i < cr; i++) { |
715 | int p = indices2[i]; |
716 | while (j < cr && indices1[j] < p) |
717 | j++; |
718 | if (usage->cube[p] && (j >= cr || indices1[j] != p)) { |
7c568a48 |
719 | #ifdef STANDALONE_SOLVER |
720 | if (solver_show_working) { |
721 | int px, py, pn; |
722 | |
723 | if (!ret) { |
724 | va_list ap; |
fdb3b29a |
725 | printf("%*s", solver_recurse_depth*4, ""); |
7c568a48 |
726 | va_start(ap, fmt); |
727 | vprintf(fmt, ap); |
728 | va_end(ap); |
729 | printf(":\n"); |
730 | } |
731 | |
732 | pn = 1 + p % cr; |
fbd0fc79 |
733 | px = p / cr; |
734 | py = px / cr; |
735 | px %= cr; |
7c568a48 |
736 | |
ab362080 |
737 | printf("%*s ruling out %d at (%d,%d)\n", |
fbd0fc79 |
738 | solver_recurse_depth*4, "", pn, 1+px, 1+py); |
7c568a48 |
739 | } |
740 | #endif |
ab362080 |
741 | ret = +1; /* we did something */ |
7c568a48 |
742 | usage->cube[p] = 0; |
743 | } |
744 | } |
745 | |
746 | return ret; |
747 | } |
748 | |
ab362080 |
749 | struct solver_scratch { |
ab53eb64 |
750 | unsigned char *grid, *rowidx, *colidx, *set; |
44bf5f6f |
751 | int *neighbours, *bfsqueue; |
fbd0fc79 |
752 | int *indexlist, *indexlist2; |
44bf5f6f |
753 | #ifdef STANDALONE_SOLVER |
754 | int *bfsprev; |
755 | #endif |
ab53eb64 |
756 | }; |
757 | |
ab362080 |
758 | static int solver_set(struct solver_usage *usage, |
759 | struct solver_scratch *scratch, |
fbd0fc79 |
760 | int *indices |
7c568a48 |
761 | #ifdef STANDALONE_SOLVER |
762 | , char *fmt, ... |
763 | #endif |
764 | ) |
765 | { |
fbd0fc79 |
766 | int cr = usage->cr; |
7c568a48 |
767 | int i, j, n, count; |
ab53eb64 |
768 | unsigned char *grid = scratch->grid; |
769 | unsigned char *rowidx = scratch->rowidx; |
770 | unsigned char *colidx = scratch->colidx; |
771 | unsigned char *set = scratch->set; |
7c568a48 |
772 | |
773 | /* |
774 | * We are passed a cr-by-cr matrix of booleans. Our first job |
775 | * is to winnow it by finding any definite placements - i.e. |
776 | * any row with a solitary 1 - and discarding that row and the |
777 | * column containing the 1. |
778 | */ |
779 | memset(rowidx, TRUE, cr); |
780 | memset(colidx, TRUE, cr); |
781 | for (i = 0; i < cr; i++) { |
782 | int count = 0, first = -1; |
783 | for (j = 0; j < cr; j++) |
fbd0fc79 |
784 | if (usage->cube[indices[i*cr+j]]) |
7c568a48 |
785 | first = j, count++; |
ab362080 |
786 | |
787 | /* |
788 | * If count == 0, then there's a row with no 1s at all and |
789 | * the puzzle is internally inconsistent. However, we ought |
790 | * to have caught this already during the simpler reasoning |
791 | * methods, so we can safely fail an assertion if we reach |
792 | * this point here. |
793 | */ |
794 | assert(count > 0); |
7c568a48 |
795 | if (count == 1) |
796 | rowidx[i] = colidx[first] = FALSE; |
797 | } |
798 | |
799 | /* |
800 | * Convert each of rowidx/colidx from a list of 0s and 1s to a |
801 | * list of the indices of the 1s. |
802 | */ |
803 | for (i = j = 0; i < cr; i++) |
804 | if (rowidx[i]) |
805 | rowidx[j++] = i; |
806 | n = j; |
807 | for (i = j = 0; i < cr; i++) |
808 | if (colidx[i]) |
809 | colidx[j++] = i; |
810 | assert(n == j); |
811 | |
812 | /* |
813 | * And create the smaller matrix. |
814 | */ |
815 | for (i = 0; i < n; i++) |
816 | for (j = 0; j < n; j++) |
fbd0fc79 |
817 | grid[i*cr+j] = usage->cube[indices[rowidx[i]*cr+colidx[j]]]; |
7c568a48 |
818 | |
819 | /* |
820 | * Having done that, we now have a matrix in which every row |
821 | * has at least two 1s in. Now we search to see if we can find |
822 | * a rectangle of zeroes (in the set-theoretic sense of |
823 | * `rectangle', i.e. a subset of rows crossed with a subset of |
824 | * columns) whose width and height add up to n. |
825 | */ |
826 | |
827 | memset(set, 0, n); |
828 | count = 0; |
829 | while (1) { |
830 | /* |
831 | * We have a candidate set. If its size is <=1 or >=n-1 |
832 | * then we move on immediately. |
833 | */ |
834 | if (count > 1 && count < n-1) { |
835 | /* |
836 | * The number of rows we need is n-count. See if we can |
837 | * find that many rows which each have a zero in all |
838 | * the positions listed in `set'. |
839 | */ |
840 | int rows = 0; |
841 | for (i = 0; i < n; i++) { |
842 | int ok = TRUE; |
843 | for (j = 0; j < n; j++) |
844 | if (set[j] && grid[i*cr+j]) { |
845 | ok = FALSE; |
846 | break; |
847 | } |
848 | if (ok) |
849 | rows++; |
850 | } |
851 | |
852 | /* |
853 | * We expect never to be able to get _more_ than |
854 | * n-count suitable rows: this would imply that (for |
855 | * example) there are four numbers which between them |
856 | * have at most three possible positions, and hence it |
857 | * indicates a faulty deduction before this point or |
858 | * even a bogus clue. |
859 | */ |
ab362080 |
860 | if (rows > n - count) { |
861 | #ifdef STANDALONE_SOLVER |
862 | if (solver_show_working) { |
fdb3b29a |
863 | va_list ap; |
ab362080 |
864 | printf("%*s", solver_recurse_depth*4, |
865 | ""); |
ab362080 |
866 | va_start(ap, fmt); |
867 | vprintf(fmt, ap); |
868 | va_end(ap); |
869 | printf(":\n%*s contradiction reached\n", |
870 | solver_recurse_depth*4, ""); |
871 | } |
872 | #endif |
873 | return -1; |
874 | } |
875 | |
7c568a48 |
876 | if (rows >= n - count) { |
877 | int progress = FALSE; |
878 | |
879 | /* |
880 | * We've got one! Now, for each row which _doesn't_ |
881 | * satisfy the criterion, eliminate all its set |
882 | * bits in the positions _not_ listed in `set'. |
ab362080 |
883 | * Return +1 (meaning progress has been made) if we |
884 | * successfully eliminated anything at all. |
7c568a48 |
885 | * |
886 | * This involves referring back through |
887 | * rowidx/colidx in order to work out which actual |
888 | * positions in the cube to meddle with. |
889 | */ |
890 | for (i = 0; i < n; i++) { |
891 | int ok = TRUE; |
892 | for (j = 0; j < n; j++) |
893 | if (set[j] && grid[i*cr+j]) { |
894 | ok = FALSE; |
895 | break; |
896 | } |
897 | if (!ok) { |
898 | for (j = 0; j < n; j++) |
899 | if (!set[j] && grid[i*cr+j]) { |
fbd0fc79 |
900 | int fpos = indices[rowidx[i]*cr+colidx[j]]; |
7c568a48 |
901 | #ifdef STANDALONE_SOLVER |
902 | if (solver_show_working) { |
903 | int px, py, pn; |
ab362080 |
904 | |
7c568a48 |
905 | if (!progress) { |
fdb3b29a |
906 | va_list ap; |
ab362080 |
907 | printf("%*s", solver_recurse_depth*4, |
908 | ""); |
7c568a48 |
909 | va_start(ap, fmt); |
910 | vprintf(fmt, ap); |
911 | va_end(ap); |
912 | printf(":\n"); |
913 | } |
914 | |
915 | pn = 1 + fpos % cr; |
fbd0fc79 |
916 | px = fpos / cr; |
917 | py = px / cr; |
918 | px %= cr; |
7c568a48 |
919 | |
ab362080 |
920 | printf("%*s ruling out %d at (%d,%d)\n", |
921 | solver_recurse_depth*4, "", |
fbd0fc79 |
922 | pn, 1+px, 1+py); |
7c568a48 |
923 | } |
924 | #endif |
925 | progress = TRUE; |
926 | usage->cube[fpos] = FALSE; |
927 | } |
928 | } |
929 | } |
930 | |
931 | if (progress) { |
ab362080 |
932 | return +1; |
7c568a48 |
933 | } |
934 | } |
935 | } |
936 | |
937 | /* |
938 | * Binary increment: change the rightmost 0 to a 1, and |
939 | * change all 1s to the right of it to 0s. |
940 | */ |
941 | i = n; |
942 | while (i > 0 && set[i-1]) |
943 | set[--i] = 0, count--; |
944 | if (i > 0) |
945 | set[--i] = 1, count++; |
946 | else |
947 | break; /* done */ |
948 | } |
949 | |
ab362080 |
950 | return 0; |
7c568a48 |
951 | } |
952 | |
13c4d60d |
953 | /* |
44bf5f6f |
954 | * Look for forcing chains. A forcing chain is a path of |
955 | * pairwise-exclusive squares (i.e. each pair of adjacent squares |
956 | * in the path are in the same row, column or block) with the |
957 | * following properties: |
958 | * |
959 | * (a) Each square on the path has precisely two possible numbers. |
960 | * |
961 | * (b) Each pair of squares which are adjacent on the path share |
fbd0fc79 |
962 | * at least one possible number in common. |
44bf5f6f |
963 | * |
964 | * (c) Each square in the middle of the path shares _both_ of its |
fbd0fc79 |
965 | * numbers with at least one of its neighbours (not the same |
966 | * one with both neighbours). |
44bf5f6f |
967 | * |
968 | * These together imply that at least one of the possible number |
969 | * choices at one end of the path forces _all_ the rest of the |
970 | * numbers along the path. In order to make real use of this, we |
971 | * need further properties: |
972 | * |
fbd0fc79 |
973 | * (c) Ruling out some number N from the square at one end of the |
974 | * path forces the square at the other end to take the same |
975 | * number N. |
44bf5f6f |
976 | * |
977 | * (d) The two end squares are both in line with some third |
fbd0fc79 |
978 | * square. |
44bf5f6f |
979 | * |
980 | * (e) That third square currently has N as a possibility. |
981 | * |
982 | * If we can find all of that lot, we can deduce that at least one |
983 | * of the two ends of the forcing chain has number N, and that |
984 | * therefore the mutually adjacent third square does not. |
985 | * |
986 | * To find forcing chains, we're going to start a bfs at each |
987 | * suitable square, once for each of its two possible numbers. |
988 | */ |
989 | static int solver_forcing(struct solver_usage *usage, |
990 | struct solver_scratch *scratch) |
991 | { |
fbd0fc79 |
992 | int cr = usage->cr; |
44bf5f6f |
993 | int *bfsqueue = scratch->bfsqueue; |
994 | #ifdef STANDALONE_SOLVER |
995 | int *bfsprev = scratch->bfsprev; |
996 | #endif |
997 | unsigned char *number = scratch->grid; |
998 | int *neighbours = scratch->neighbours; |
999 | int x, y; |
1000 | |
1001 | for (y = 0; y < cr; y++) |
1002 | for (x = 0; x < cr; x++) { |
1003 | int count, t, n; |
1004 | |
1005 | /* |
1006 | * If this square doesn't have exactly two candidate |
1007 | * numbers, don't try it. |
1008 | * |
1009 | * In this loop we also sum the candidate numbers, |
1010 | * which is a nasty hack to allow us to quickly find |
1011 | * `the other one' (since we will shortly know there |
1012 | * are exactly two). |
1013 | */ |
1014 | for (count = t = 0, n = 1; n <= cr; n++) |
1015 | if (cube(x, y, n)) |
1016 | count++, t += n; |
1017 | if (count != 2) |
1018 | continue; |
1019 | |
1020 | /* |
1021 | * Now attempt a bfs for each candidate. |
1022 | */ |
1023 | for (n = 1; n <= cr; n++) |
1024 | if (cube(x, y, n)) { |
1025 | int orign, currn, head, tail; |
1026 | |
1027 | /* |
1028 | * Begin a bfs. |
1029 | */ |
1030 | orign = n; |
1031 | |
1032 | memset(number, cr+1, cr*cr); |
1033 | head = tail = 0; |
1034 | bfsqueue[tail++] = y*cr+x; |
1035 | #ifdef STANDALONE_SOLVER |
1036 | bfsprev[y*cr+x] = -1; |
1037 | #endif |
1038 | number[y*cr+x] = t - n; |
1039 | |
1040 | while (head < tail) { |
fbd0fc79 |
1041 | int xx, yy, nneighbours, xt, yt, i; |
44bf5f6f |
1042 | |
1043 | xx = bfsqueue[head++]; |
1044 | yy = xx / cr; |
1045 | xx %= cr; |
1046 | |
1047 | currn = number[yy*cr+xx]; |
1048 | |
1049 | /* |
1050 | * Find neighbours of yy,xx. |
1051 | */ |
1052 | nneighbours = 0; |
1053 | for (yt = 0; yt < cr; yt++) |
1054 | neighbours[nneighbours++] = yt*cr+xx; |
1055 | for (xt = 0; xt < cr; xt++) |
1056 | neighbours[nneighbours++] = yy*cr+xt; |
fbd0fc79 |
1057 | xt = usage->blocks->whichblock[yy*cr+xx]; |
1058 | for (yt = 0; yt < cr; yt++) |
1059 | neighbours[nneighbours++] = usage->blocks->blocks[xt][yt]; |
1060 | if (usage->diag) { |
1061 | int sqindex = yy*cr+xx; |
1062 | if (ondiag0(sqindex)) { |
1063 | for (i = 0; i < cr; i++) |
1064 | neighbours[nneighbours++] = diag0(i); |
1065 | } |
1066 | if (ondiag1(sqindex)) { |
1067 | for (i = 0; i < cr; i++) |
1068 | neighbours[nneighbours++] = diag1(i); |
1069 | } |
1070 | } |
44bf5f6f |
1071 | |
1072 | /* |
1073 | * Try visiting each of those neighbours. |
1074 | */ |
1075 | for (i = 0; i < nneighbours; i++) { |
1076 | int cc, tt, nn; |
1077 | |
1078 | xt = neighbours[i] % cr; |
1079 | yt = neighbours[i] / cr; |
1080 | |
1081 | /* |
1082 | * We need this square to not be |
1083 | * already visited, and to include |
1084 | * currn as a possible number. |
1085 | */ |
1086 | if (number[yt*cr+xt] <= cr) |
1087 | continue; |
1088 | if (!cube(xt, yt, currn)) |
1089 | continue; |
1090 | |
1091 | /* |
1092 | * Don't visit _this_ square a second |
1093 | * time! |
1094 | */ |
1095 | if (xt == xx && yt == yy) |
1096 | continue; |
1097 | |
1098 | /* |
1099 | * To continue with the bfs, we need |
1100 | * this square to have exactly two |
1101 | * possible numbers. |
1102 | */ |
1103 | for (cc = tt = 0, nn = 1; nn <= cr; nn++) |
1104 | if (cube(xt, yt, nn)) |
1105 | cc++, tt += nn; |
1106 | if (cc == 2) { |
1107 | bfsqueue[tail++] = yt*cr+xt; |
1108 | #ifdef STANDALONE_SOLVER |
1109 | bfsprev[yt*cr+xt] = yy*cr+xx; |
1110 | #endif |
1111 | number[yt*cr+xt] = tt - currn; |
1112 | } |
1113 | |
1114 | /* |
1115 | * One other possibility is that this |
1116 | * might be the square in which we can |
1117 | * make a real deduction: if it's |
1118 | * adjacent to x,y, and currn is equal |
1119 | * to the original number we ruled out. |
1120 | */ |
1121 | if (currn == orign && |
1122 | (xt == x || yt == y || |
fbd0fc79 |
1123 | (usage->blocks->whichblock[yt*cr+xt] == usage->blocks->whichblock[y*cr+x]) || |
1124 | (usage->diag && ((ondiag0(yt*cr+xt) && ondiag0(y*cr+x)) || |
1125 | (ondiag1(yt*cr+xt) && ondiag1(y*cr+x)))))) { |
44bf5f6f |
1126 | #ifdef STANDALONE_SOLVER |
1127 | if (solver_show_working) { |
1128 | char *sep = ""; |
1129 | int xl, yl; |
1130 | printf("%*sforcing chain, %d at ends of ", |
1131 | solver_recurse_depth*4, "", orign); |
1132 | xl = xx; |
1133 | yl = yy; |
1134 | while (1) { |
1135 | printf("%s(%d,%d)", sep, 1+xl, |
fbd0fc79 |
1136 | 1+yl); |
44bf5f6f |
1137 | xl = bfsprev[yl*cr+xl]; |
1138 | if (xl < 0) |
1139 | break; |
1140 | yl = xl / cr; |
1141 | xl %= cr; |
1142 | sep = "-"; |
1143 | } |
1144 | printf("\n%*s ruling out %d at (%d,%d)\n", |
1145 | solver_recurse_depth*4, "", |
fbd0fc79 |
1146 | orign, 1+xt, 1+yt); |
44bf5f6f |
1147 | } |
1148 | #endif |
1149 | cube(xt, yt, orign) = FALSE; |
1150 | return 1; |
1151 | } |
1152 | } |
1153 | } |
1154 | } |
1155 | } |
1156 | |
1157 | return 0; |
1158 | } |
1159 | |
ab362080 |
1160 | static struct solver_scratch *solver_new_scratch(struct solver_usage *usage) |
ab53eb64 |
1161 | { |
ab362080 |
1162 | struct solver_scratch *scratch = snew(struct solver_scratch); |
ab53eb64 |
1163 | int cr = usage->cr; |
1164 | scratch->grid = snewn(cr*cr, unsigned char); |
1165 | scratch->rowidx = snewn(cr, unsigned char); |
1166 | scratch->colidx = snewn(cr, unsigned char); |
1167 | scratch->set = snewn(cr, unsigned char); |
fbd0fc79 |
1168 | scratch->neighbours = snewn(5*cr, int); |
44bf5f6f |
1169 | scratch->bfsqueue = snewn(cr*cr, int); |
1170 | #ifdef STANDALONE_SOLVER |
1171 | scratch->bfsprev = snewn(cr*cr, int); |
1172 | #endif |
fbd0fc79 |
1173 | scratch->indexlist = snewn(cr*cr, int); /* used for set elimination */ |
1174 | scratch->indexlist2 = snewn(cr, int); /* only used for intersect() */ |
ab53eb64 |
1175 | return scratch; |
1176 | } |
1177 | |
ab362080 |
1178 | static void solver_free_scratch(struct solver_scratch *scratch) |
ab53eb64 |
1179 | { |
44bf5f6f |
1180 | #ifdef STANDALONE_SOLVER |
1181 | sfree(scratch->bfsprev); |
1182 | #endif |
1183 | sfree(scratch->bfsqueue); |
1184 | sfree(scratch->neighbours); |
ab53eb64 |
1185 | sfree(scratch->set); |
1186 | sfree(scratch->colidx); |
1187 | sfree(scratch->rowidx); |
1188 | sfree(scratch->grid); |
fbd0fc79 |
1189 | sfree(scratch->indexlist); |
1190 | sfree(scratch->indexlist2); |
ab53eb64 |
1191 | sfree(scratch); |
1192 | } |
1193 | |
fbd0fc79 |
1194 | static int solver(int cr, struct block_structure *blocks, int xtype, |
1195 | digit *grid, int maxdiff) |
1d8e8ad8 |
1196 | { |
ab362080 |
1197 | struct solver_usage *usage; |
1198 | struct solver_scratch *scratch; |
fbd0fc79 |
1199 | int x, y, b, i, n, ret; |
7c568a48 |
1200 | int diff = DIFF_BLOCK; |
1d8e8ad8 |
1201 | |
1202 | /* |
1203 | * Set up a usage structure as a clean slate (everything |
1204 | * possible). |
1205 | */ |
ab362080 |
1206 | usage = snew(struct solver_usage); |
1d8e8ad8 |
1207 | usage->cr = cr; |
fbd0fc79 |
1208 | usage->blocks = blocks; |
1d8e8ad8 |
1209 | usage->cube = snewn(cr*cr*cr, unsigned char); |
1210 | usage->grid = grid; /* write straight back to the input */ |
1211 | memset(usage->cube, TRUE, cr*cr*cr); |
1212 | |
1213 | usage->row = snewn(cr * cr, unsigned char); |
1214 | usage->col = snewn(cr * cr, unsigned char); |
1215 | usage->blk = snewn(cr * cr, unsigned char); |
1216 | memset(usage->row, FALSE, cr * cr); |
1217 | memset(usage->col, FALSE, cr * cr); |
1218 | memset(usage->blk, FALSE, cr * cr); |
1219 | |
fbd0fc79 |
1220 | if (xtype) { |
1221 | usage->diag = snewn(cr * 2, unsigned char); |
1222 | memset(usage->diag, FALSE, cr * 2); |
1223 | } else |
1224 | usage->diag = NULL; |
1225 | |
ab362080 |
1226 | scratch = solver_new_scratch(usage); |
ab53eb64 |
1227 | |
1d8e8ad8 |
1228 | /* |
1229 | * Place all the clue numbers we are given. |
1230 | */ |
1231 | for (x = 0; x < cr; x++) |
1232 | for (y = 0; y < cr; y++) |
1233 | if (grid[y*cr+x]) |
fbd0fc79 |
1234 | solver_place(usage, x, y, grid[y*cr+x]); |
1d8e8ad8 |
1235 | |
1236 | /* |
1237 | * Now loop over the grid repeatedly trying all permitted modes |
1238 | * of reasoning. The loop terminates if we complete an |
1239 | * iteration without making any progress; we then return |
1240 | * failure or success depending on whether the grid is full or |
1241 | * not. |
1242 | */ |
1243 | while (1) { |
7c568a48 |
1244 | /* |
1245 | * I'd like to write `continue;' inside each of the |
1246 | * following loops, so that the solver returns here after |
1247 | * making some progress. However, I can't specify that I |
1248 | * want to continue an outer loop rather than the innermost |
1249 | * one, so I'm apologetically resorting to a goto. |
1250 | */ |
3ddae0ff |
1251 | cont: |
1252 | |
1d8e8ad8 |
1253 | /* |
1254 | * Blockwise positional elimination. |
1255 | */ |
fbd0fc79 |
1256 | for (b = 0; b < cr; b++) |
1257 | for (n = 1; n <= cr; n++) |
1258 | if (!usage->blk[b*cr+n-1]) { |
1259 | for (i = 0; i < cr; i++) |
1260 | scratch->indexlist[i] = cubepos2(usage->blocks->blocks[b][i],n); |
1261 | ret = solver_elim(usage, scratch->indexlist |
7c568a48 |
1262 | #ifdef STANDALONE_SOLVER |
fbd0fc79 |
1263 | , "positional elimination," |
1264 | " %d in block %s", n, |
1265 | usage->blocks->blocknames[b] |
7c568a48 |
1266 | #endif |
fbd0fc79 |
1267 | ); |
1268 | if (ret < 0) { |
1269 | diff = DIFF_IMPOSSIBLE; |
1270 | goto got_result; |
1271 | } else if (ret > 0) { |
1272 | diff = max(diff, DIFF_BLOCK); |
1273 | goto cont; |
1274 | } |
1275 | } |
1d8e8ad8 |
1276 | |
ab362080 |
1277 | if (maxdiff <= DIFF_BLOCK) |
1278 | break; |
1279 | |
1d8e8ad8 |
1280 | /* |
1281 | * Row-wise positional elimination. |
1282 | */ |
1283 | for (y = 0; y < cr; y++) |
1284 | for (n = 1; n <= cr; n++) |
ab362080 |
1285 | if (!usage->row[y*cr+n-1]) { |
fbd0fc79 |
1286 | for (x = 0; x < cr; x++) |
1287 | scratch->indexlist[x] = cubepos(x, y, n); |
1288 | ret = solver_elim(usage, scratch->indexlist |
7c568a48 |
1289 | #ifdef STANDALONE_SOLVER |
ab362080 |
1290 | , "positional elimination," |
fbd0fc79 |
1291 | " %d in row %d", n, 1+y |
7c568a48 |
1292 | #endif |
ab362080 |
1293 | ); |
1294 | if (ret < 0) { |
1295 | diff = DIFF_IMPOSSIBLE; |
1296 | goto got_result; |
1297 | } else if (ret > 0) { |
1298 | diff = max(diff, DIFF_SIMPLE); |
1299 | goto cont; |
1300 | } |
7c568a48 |
1301 | } |
1d8e8ad8 |
1302 | /* |
1303 | * Column-wise positional elimination. |
1304 | */ |
1305 | for (x = 0; x < cr; x++) |
1306 | for (n = 1; n <= cr; n++) |
ab362080 |
1307 | if (!usage->col[x*cr+n-1]) { |
fbd0fc79 |
1308 | for (y = 0; y < cr; y++) |
1309 | scratch->indexlist[y] = cubepos(x, y, n); |
1310 | ret = solver_elim(usage, scratch->indexlist |
7c568a48 |
1311 | #ifdef STANDALONE_SOLVER |
ab362080 |
1312 | , "positional elimination," |
1313 | " %d in column %d", n, 1+x |
7c568a48 |
1314 | #endif |
ab362080 |
1315 | ); |
1316 | if (ret < 0) { |
1317 | diff = DIFF_IMPOSSIBLE; |
1318 | goto got_result; |
1319 | } else if (ret > 0) { |
1320 | diff = max(diff, DIFF_SIMPLE); |
1321 | goto cont; |
1322 | } |
7c568a48 |
1323 | } |
1d8e8ad8 |
1324 | |
1325 | /* |
fbd0fc79 |
1326 | * X-diagonal positional elimination. |
1327 | */ |
1328 | if (usage->diag) { |
1329 | for (n = 1; n <= cr; n++) |
1330 | if (!usage->diag[n-1]) { |
1331 | for (i = 0; i < cr; i++) |
1332 | scratch->indexlist[i] = cubepos2(diag0(i), n); |
1333 | ret = solver_elim(usage, scratch->indexlist |
1334 | #ifdef STANDALONE_SOLVER |
1335 | , "positional elimination," |
1336 | " %d in \\-diagonal", n |
1337 | #endif |
1338 | ); |
1339 | if (ret < 0) { |
1340 | diff = DIFF_IMPOSSIBLE; |
1341 | goto got_result; |
1342 | } else if (ret > 0) { |
1343 | diff = max(diff, DIFF_SIMPLE); |
1344 | goto cont; |
1345 | } |
1346 | } |
1347 | for (n = 1; n <= cr; n++) |
1348 | if (!usage->diag[cr+n-1]) { |
1349 | for (i = 0; i < cr; i++) |
1350 | scratch->indexlist[i] = cubepos2(diag1(i), n); |
1351 | ret = solver_elim(usage, scratch->indexlist |
1352 | #ifdef STANDALONE_SOLVER |
1353 | , "positional elimination," |
1354 | " %d in /-diagonal", n |
1355 | #endif |
1356 | ); |
1357 | if (ret < 0) { |
1358 | diff = DIFF_IMPOSSIBLE; |
1359 | goto got_result; |
1360 | } else if (ret > 0) { |
1361 | diff = max(diff, DIFF_SIMPLE); |
1362 | goto cont; |
1363 | } |
1364 | } |
1365 | } |
1366 | |
1367 | /* |
1d8e8ad8 |
1368 | * Numeric elimination. |
1369 | */ |
1370 | for (x = 0; x < cr; x++) |
1371 | for (y = 0; y < cr; y++) |
fbd0fc79 |
1372 | if (!usage->grid[y*cr+x]) { |
1373 | for (n = 1; n <= cr; n++) |
1374 | scratch->indexlist[n-1] = cubepos(x, y, n); |
1375 | ret = solver_elim(usage, scratch->indexlist |
7c568a48 |
1376 | #ifdef STANDALONE_SOLVER |
fbd0fc79 |
1377 | , "numeric elimination at (%d,%d)", |
1378 | 1+x, 1+y |
7c568a48 |
1379 | #endif |
ab362080 |
1380 | ); |
1381 | if (ret < 0) { |
1382 | diff = DIFF_IMPOSSIBLE; |
1383 | goto got_result; |
1384 | } else if (ret > 0) { |
1385 | diff = max(diff, DIFF_SIMPLE); |
1386 | goto cont; |
1387 | } |
7c568a48 |
1388 | } |
1389 | |
ab362080 |
1390 | if (maxdiff <= DIFF_SIMPLE) |
1391 | break; |
1392 | |
7c568a48 |
1393 | /* |
1394 | * Intersectional analysis, rows vs blocks. |
1395 | */ |
1396 | for (y = 0; y < cr; y++) |
fbd0fc79 |
1397 | for (b = 0; b < cr; b++) |
1398 | for (n = 1; n <= cr; n++) { |
1399 | if (usage->row[y*cr+n-1] || |
1400 | usage->blk[b*cr+n-1]) |
1401 | continue; |
1402 | for (i = 0; i < cr; i++) { |
1403 | scratch->indexlist[i] = cubepos(i, y, n); |
1404 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
1405 | } |
ab362080 |
1406 | /* |
1407 | * solver_intersect() never returns -1. |
1408 | */ |
fbd0fc79 |
1409 | if (solver_intersect(usage, scratch->indexlist, |
1410 | scratch->indexlist2 |
7c568a48 |
1411 | #ifdef STANDALONE_SOLVER |
1412 | , "intersectional analysis," |
fbd0fc79 |
1413 | " %d in row %d vs block %s", |
1414 | n, 1+y, usage->blocks->blocknames[b] |
7c568a48 |
1415 | #endif |
1416 | ) || |
fbd0fc79 |
1417 | solver_intersect(usage, scratch->indexlist2, |
1418 | scratch->indexlist |
7c568a48 |
1419 | #ifdef STANDALONE_SOLVER |
1420 | , "intersectional analysis," |
fbd0fc79 |
1421 | " %d in block %s vs row %d", |
1422 | n, usage->blocks->blocknames[b], 1+y |
7c568a48 |
1423 | #endif |
fbd0fc79 |
1424 | )) { |
7c568a48 |
1425 | diff = max(diff, DIFF_INTERSECT); |
1426 | goto cont; |
1427 | } |
fbd0fc79 |
1428 | } |
7c568a48 |
1429 | |
1430 | /* |
1431 | * Intersectional analysis, columns vs blocks. |
1432 | */ |
1433 | for (x = 0; x < cr; x++) |
fbd0fc79 |
1434 | for (b = 0; b < cr; b++) |
1435 | for (n = 1; n <= cr; n++) { |
1436 | if (usage->col[x*cr+n-1] || |
1437 | usage->blk[b*cr+n-1]) |
1438 | continue; |
1439 | for (i = 0; i < cr; i++) { |
1440 | scratch->indexlist[i] = cubepos(x, i, n); |
1441 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
1442 | } |
1443 | if (solver_intersect(usage, scratch->indexlist, |
1444 | scratch->indexlist2 |
1445 | #ifdef STANDALONE_SOLVER |
1446 | , "intersectional analysis," |
1447 | " %d in column %d vs block %s", |
1448 | n, 1+x, usage->blocks->blocknames[b] |
1449 | #endif |
1450 | ) || |
1451 | solver_intersect(usage, scratch->indexlist2, |
1452 | scratch->indexlist |
1453 | #ifdef STANDALONE_SOLVER |
1454 | , "intersectional analysis," |
1455 | " %d in block %s vs column %d", |
1456 | n, usage->blocks->blocknames[b], 1+x |
1457 | #endif |
1458 | )) { |
1459 | diff = max(diff, DIFF_INTERSECT); |
1460 | goto cont; |
1461 | } |
1462 | } |
1463 | |
1464 | if (usage->diag) { |
1465 | /* |
1466 | * Intersectional analysis, \-diagonal vs blocks. |
1467 | */ |
1468 | for (b = 0; b < cr; b++) |
1469 | for (n = 1; n <= cr; n++) { |
1470 | if (usage->diag[n-1] || |
1471 | usage->blk[b*cr+n-1]) |
1472 | continue; |
1473 | for (i = 0; i < cr; i++) { |
1474 | scratch->indexlist[i] = cubepos2(diag0(i), n); |
1475 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
1476 | } |
1477 | if (solver_intersect(usage, scratch->indexlist, |
1478 | scratch->indexlist2 |
1479 | #ifdef STANDALONE_SOLVER |
1480 | , "intersectional analysis," |
1481 | " %d in \\-diagonal vs block %s", |
1482 | n, 1+x, usage->blocks->blocknames[b] |
1483 | #endif |
1484 | ) || |
1485 | solver_intersect(usage, scratch->indexlist2, |
1486 | scratch->indexlist |
1487 | #ifdef STANDALONE_SOLVER |
1488 | , "intersectional analysis," |
1489 | " %d in block %s vs \\-diagonal", |
1490 | n, usage->blocks->blocknames[b], 1+x |
1491 | #endif |
1492 | )) { |
1493 | diff = max(diff, DIFF_INTERSECT); |
1494 | goto cont; |
1495 | } |
1496 | } |
1497 | |
1498 | /* |
1499 | * Intersectional analysis, /-diagonal vs blocks. |
1500 | */ |
1501 | for (b = 0; b < cr; b++) |
1502 | for (n = 1; n <= cr; n++) { |
1503 | if (usage->diag[cr+n-1] || |
1504 | usage->blk[b*cr+n-1]) |
1505 | continue; |
1506 | for (i = 0; i < cr; i++) { |
1507 | scratch->indexlist[i] = cubepos2(diag1(i), n); |
1508 | scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n); |
1509 | } |
1510 | if (solver_intersect(usage, scratch->indexlist, |
1511 | scratch->indexlist2 |
7c568a48 |
1512 | #ifdef STANDALONE_SOLVER |
1513 | , "intersectional analysis," |
fbd0fc79 |
1514 | " %d in /-diagonal vs block %s", |
1515 | n, 1+x, usage->blocks->blocknames[b] |
7c568a48 |
1516 | #endif |
1517 | ) || |
fbd0fc79 |
1518 | solver_intersect(usage, scratch->indexlist2, |
1519 | scratch->indexlist |
7c568a48 |
1520 | #ifdef STANDALONE_SOLVER |
1521 | , "intersectional analysis," |
fbd0fc79 |
1522 | " %d in block %s vs /-diagonal", |
1523 | n, usage->blocks->blocknames[b], 1+x |
7c568a48 |
1524 | #endif |
fbd0fc79 |
1525 | )) { |
7c568a48 |
1526 | diff = max(diff, DIFF_INTERSECT); |
1527 | goto cont; |
1528 | } |
fbd0fc79 |
1529 | } |
1530 | } |
7c568a48 |
1531 | |
ab362080 |
1532 | if (maxdiff <= DIFF_INTERSECT) |
1533 | break; |
1534 | |
7c568a48 |
1535 | /* |
1536 | * Blockwise set elimination. |
1537 | */ |
fbd0fc79 |
1538 | for (b = 0; b < cr; b++) { |
1539 | for (i = 0; i < cr; i++) |
1540 | for (n = 1; n <= cr; n++) |
1541 | scratch->indexlist[i*cr+n-1] = cubepos2(usage->blocks->blocks[b][i], n); |
1542 | ret = solver_set(usage, scratch, scratch->indexlist |
7c568a48 |
1543 | #ifdef STANDALONE_SOLVER |
fbd0fc79 |
1544 | , "set elimination, block %s", |
1545 | usage->blocks->blocknames[b] |
7c568a48 |
1546 | #endif |
ab362080 |
1547 | ); |
fbd0fc79 |
1548 | if (ret < 0) { |
1549 | diff = DIFF_IMPOSSIBLE; |
1550 | goto got_result; |
1551 | } else if (ret > 0) { |
1552 | diff = max(diff, DIFF_SET); |
1553 | goto cont; |
ab362080 |
1554 | } |
fbd0fc79 |
1555 | } |
7c568a48 |
1556 | |
1557 | /* |
1558 | * Row-wise set elimination. |
1559 | */ |
ab362080 |
1560 | for (y = 0; y < cr; y++) { |
fbd0fc79 |
1561 | for (x = 0; x < cr; x++) |
1562 | for (n = 1; n <= cr; n++) |
1563 | scratch->indexlist[x*cr+n-1] = cubepos(x, y, n); |
1564 | ret = solver_set(usage, scratch, scratch->indexlist |
7c568a48 |
1565 | #ifdef STANDALONE_SOLVER |
fbd0fc79 |
1566 | , "set elimination, row %d", 1+y |
7c568a48 |
1567 | #endif |
ab362080 |
1568 | ); |
1569 | if (ret < 0) { |
1570 | diff = DIFF_IMPOSSIBLE; |
1571 | goto got_result; |
1572 | } else if (ret > 0) { |
1573 | diff = max(diff, DIFF_SET); |
1574 | goto cont; |
1575 | } |
1576 | } |
7c568a48 |
1577 | |
1578 | /* |
1579 | * Column-wise set elimination. |
1580 | */ |
ab362080 |
1581 | for (x = 0; x < cr; x++) { |
fbd0fc79 |
1582 | for (y = 0; y < cr; y++) |
1583 | for (n = 1; n <= cr; n++) |
1584 | scratch->indexlist[y*cr+n-1] = cubepos(x, y, n); |
1585 | ret = solver_set(usage, scratch, scratch->indexlist |
7c568a48 |
1586 | #ifdef STANDALONE_SOLVER |
ab362080 |
1587 | , "set elimination, column %d", 1+x |
7c568a48 |
1588 | #endif |
ab362080 |
1589 | ); |
1590 | if (ret < 0) { |
1591 | diff = DIFF_IMPOSSIBLE; |
1592 | goto got_result; |
1593 | } else if (ret > 0) { |
1594 | diff = max(diff, DIFF_SET); |
1595 | goto cont; |
1596 | } |
1597 | } |
1d8e8ad8 |
1598 | |
fbd0fc79 |
1599 | if (usage->diag) { |
1600 | /* |
1601 | * \-diagonal set elimination. |
1602 | */ |
1603 | for (i = 0; i < cr; i++) |
1604 | for (n = 1; n <= cr; n++) |
1605 | scratch->indexlist[i*cr+n-1] = cubepos2(diag0(i), n); |
1606 | ret = solver_set(usage, scratch, scratch->indexlist |
1607 | #ifdef STANDALONE_SOLVER |
1608 | , "set elimination, \\-diagonal" |
1609 | #endif |
1610 | ); |
1611 | if (ret < 0) { |
1612 | diff = DIFF_IMPOSSIBLE; |
1613 | goto got_result; |
1614 | } else if (ret > 0) { |
1615 | diff = max(diff, DIFF_SET); |
1616 | goto cont; |
1617 | } |
1618 | |
1619 | /* |
1620 | * /-diagonal set elimination. |
1621 | */ |
1622 | for (i = 0; i < cr; i++) |
1623 | for (n = 1; n <= cr; n++) |
1624 | scratch->indexlist[i*cr+n-1] = cubepos2(diag1(i), n); |
1625 | ret = solver_set(usage, scratch, scratch->indexlist |
1626 | #ifdef STANDALONE_SOLVER |
1627 | , "set elimination, \\-diagonal" |
1628 | #endif |
1629 | ); |
1630 | if (ret < 0) { |
1631 | diff = DIFF_IMPOSSIBLE; |
1632 | goto got_result; |
1633 | } else if (ret > 0) { |
1634 | diff = max(diff, DIFF_SET); |
1635 | goto cont; |
1636 | } |
1637 | } |
1638 | |
1639 | if (maxdiff <= DIFF_SET) |
1640 | break; |
1641 | |
1d8e8ad8 |
1642 | /* |
44bf5f6f |
1643 | * Row-vs-column set elimination on a single number. |
1644 | */ |
1645 | for (n = 1; n <= cr; n++) { |
fbd0fc79 |
1646 | for (y = 0; y < cr; y++) |
1647 | for (x = 0; x < cr; x++) |
1648 | scratch->indexlist[y*cr+x] = cubepos(x, y, n); |
1649 | ret = solver_set(usage, scratch, scratch->indexlist |
44bf5f6f |
1650 | #ifdef STANDALONE_SOLVER |
1651 | , "positional set elimination, number %d", n |
1652 | #endif |
1653 | ); |
1654 | if (ret < 0) { |
1655 | diff = DIFF_IMPOSSIBLE; |
1656 | goto got_result; |
1657 | } else if (ret > 0) { |
1658 | diff = max(diff, DIFF_EXTREME); |
1659 | goto cont; |
1660 | } |
1661 | } |
1662 | |
44bf5f6f |
1663 | /* |
1664 | * Forcing chains. |
1665 | */ |
1666 | if (solver_forcing(usage, scratch)) { |
1667 | diff = max(diff, DIFF_EXTREME); |
1668 | goto cont; |
1669 | } |
1670 | |
13c4d60d |
1671 | /* |
1d8e8ad8 |
1672 | * If we reach here, we have made no deductions in this |
1673 | * iteration, so the algorithm terminates. |
1674 | */ |
1675 | break; |
1676 | } |
1677 | |
ab362080 |
1678 | /* |
1679 | * Last chance: if we haven't fully solved the puzzle yet, try |
1680 | * recursing based on guesses for a particular square. We pick |
1681 | * one of the most constrained empty squares we can find, which |
1682 | * has the effect of pruning the search tree as much as |
1683 | * possible. |
1684 | */ |
1685 | if (maxdiff >= DIFF_RECURSIVE) { |
947a07d6 |
1686 | int best, bestcount; |
ab362080 |
1687 | |
1688 | best = -1; |
1689 | bestcount = cr+1; |
ab362080 |
1690 | |
1691 | for (y = 0; y < cr; y++) |
1692 | for (x = 0; x < cr; x++) |
1693 | if (!grid[y*cr+x]) { |
1694 | int count; |
1695 | |
1696 | /* |
1697 | * An unfilled square. Count the number of |
1698 | * possible digits in it. |
1699 | */ |
1700 | count = 0; |
1701 | for (n = 1; n <= cr; n++) |
fbd0fc79 |
1702 | if (cube(x,y,n)) |
ab362080 |
1703 | count++; |
1704 | |
1705 | /* |
1706 | * We should have found any impossibilities |
1707 | * already, so this can safely be an assert. |
1708 | */ |
1709 | assert(count > 1); |
1710 | |
1711 | if (count < bestcount) { |
1712 | bestcount = count; |
947a07d6 |
1713 | best = y*cr+x; |
ab362080 |
1714 | } |
1715 | } |
1716 | |
1717 | if (best != -1) { |
1718 | int i, j; |
1719 | digit *list, *ingrid, *outgrid; |
1720 | |
1721 | diff = DIFF_IMPOSSIBLE; /* no solution found yet */ |
1722 | |
1723 | /* |
1724 | * Attempt recursion. |
1725 | */ |
1726 | y = best / cr; |
1727 | x = best % cr; |
1728 | |
1729 | list = snewn(cr, digit); |
1730 | ingrid = snewn(cr * cr, digit); |
1731 | outgrid = snewn(cr * cr, digit); |
1732 | memcpy(ingrid, grid, cr * cr); |
1733 | |
1734 | /* Make a list of the possible digits. */ |
1735 | for (j = 0, n = 1; n <= cr; n++) |
fbd0fc79 |
1736 | if (cube(x,y,n)) |
ab362080 |
1737 | list[j++] = n; |
1738 | |
1739 | #ifdef STANDALONE_SOLVER |
1740 | if (solver_show_working) { |
1741 | char *sep = ""; |
1742 | printf("%*srecursing on (%d,%d) [", |
49d4feb5 |
1743 | solver_recurse_depth*4, "", x + 1, y + 1); |
ab362080 |
1744 | for (i = 0; i < j; i++) { |
1745 | printf("%s%d", sep, list[i]); |
1746 | sep = " or "; |
1747 | } |
1748 | printf("]\n"); |
1749 | } |
1750 | #endif |
1751 | |
ab362080 |
1752 | /* |
1753 | * And step along the list, recursing back into the |
1754 | * main solver at every stage. |
1755 | */ |
1756 | for (i = 0; i < j; i++) { |
1757 | int ret; |
1758 | |
1759 | memcpy(outgrid, ingrid, cr * cr); |
1760 | outgrid[y*cr+x] = list[i]; |
1761 | |
1762 | #ifdef STANDALONE_SOLVER |
1763 | if (solver_show_working) |
1764 | printf("%*sguessing %d at (%d,%d)\n", |
49d4feb5 |
1765 | solver_recurse_depth*4, "", list[i], x + 1, y + 1); |
ab362080 |
1766 | solver_recurse_depth++; |
1767 | #endif |
1768 | |
fbd0fc79 |
1769 | ret = solver(cr, blocks, xtype, outgrid, maxdiff); |
ab362080 |
1770 | |
1771 | #ifdef STANDALONE_SOLVER |
1772 | solver_recurse_depth--; |
1773 | if (solver_show_working) { |
1774 | printf("%*sretracting %d at (%d,%d)\n", |
49d4feb5 |
1775 | solver_recurse_depth*4, "", list[i], x + 1, y + 1); |
ab362080 |
1776 | } |
1777 | #endif |
1778 | |
1779 | /* |
1780 | * If we have our first solution, copy it into the |
1781 | * grid we will return. |
1782 | */ |
1783 | if (diff == DIFF_IMPOSSIBLE && ret != DIFF_IMPOSSIBLE) |
1784 | memcpy(grid, outgrid, cr*cr); |
1785 | |
1786 | if (ret == DIFF_AMBIGUOUS) |
1787 | diff = DIFF_AMBIGUOUS; |
1788 | else if (ret == DIFF_IMPOSSIBLE) |
1789 | /* do not change our return value */; |
1790 | else { |
1791 | /* the recursion turned up exactly one solution */ |
1792 | if (diff == DIFF_IMPOSSIBLE) |
1793 | diff = DIFF_RECURSIVE; |
1794 | else |
1795 | diff = DIFF_AMBIGUOUS; |
1796 | } |
1797 | |
1798 | /* |
1799 | * As soon as we've found more than one solution, |
1800 | * give up immediately. |
1801 | */ |
1802 | if (diff == DIFF_AMBIGUOUS) |
1803 | break; |
1804 | } |
1805 | |
1806 | sfree(outgrid); |
1807 | sfree(ingrid); |
1808 | sfree(list); |
1809 | } |
1810 | |
1811 | } else { |
1812 | /* |
1813 | * We're forbidden to use recursion, so we just see whether |
1814 | * our grid is fully solved, and return DIFF_IMPOSSIBLE |
1815 | * otherwise. |
1816 | */ |
1817 | for (y = 0; y < cr; y++) |
1818 | for (x = 0; x < cr; x++) |
1819 | if (!grid[y*cr+x]) |
1820 | diff = DIFF_IMPOSSIBLE; |
1821 | } |
1822 | |
1823 | got_result:; |
1824 | |
1825 | #ifdef STANDALONE_SOLVER |
1826 | if (solver_show_working) |
1827 | printf("%*s%s found\n", |
1828 | solver_recurse_depth*4, "", |
1829 | diff == DIFF_IMPOSSIBLE ? "no solution" : |
1830 | diff == DIFF_AMBIGUOUS ? "multiple solutions" : |
1831 | "one solution"); |
1832 | #endif |
ab53eb64 |
1833 | |
1d8e8ad8 |
1834 | sfree(usage->cube); |
1835 | sfree(usage->row); |
1836 | sfree(usage->col); |
1837 | sfree(usage->blk); |
1838 | sfree(usage); |
1839 | |
ab362080 |
1840 | solver_free_scratch(scratch); |
1841 | |
7c568a48 |
1842 | return diff; |
1d8e8ad8 |
1843 | } |
1844 | |
1845 | /* ---------------------------------------------------------------------- |
ab362080 |
1846 | * End of solver code. |
1847 | */ |
1848 | |
1849 | /* ---------------------------------------------------------------------- |
1850 | * Solo filled-grid generator. |
1851 | * |
1852 | * This grid generator works by essentially trying to solve a grid |
1853 | * starting from no clues, and not worrying that there's more than |
1854 | * one possible solution. Unfortunately, it isn't computationally |
1855 | * feasible to do this by calling the above solver with an empty |
1856 | * grid, because that one needs to allocate a lot of scratch space |
1857 | * at every recursion level. Instead, I have a much simpler |
1858 | * algorithm which I shamelessly copied from a Python solver |
1859 | * written by Andrew Wilkinson (which is GPLed, but I've reused |
1860 | * only ideas and no code). It mostly just does the obvious |
1861 | * recursive thing: pick an empty square, put one of the possible |
1862 | * digits in it, recurse until all squares are filled, backtrack |
1863 | * and change some choices if necessary. |
1864 | * |
1865 | * The clever bit is that every time it chooses which square to |
1866 | * fill in next, it does so by counting the number of _possible_ |
1867 | * numbers that can go in each square, and it prioritises so that |
1868 | * it picks a square with the _lowest_ number of possibilities. The |
1869 | * idea is that filling in lots of the obvious bits (particularly |
1870 | * any squares with only one possibility) will cut down on the list |
1871 | * of possibilities for other squares and hence reduce the enormous |
1872 | * search space as much as possible as early as possible. |
1873 | */ |
1874 | |
1875 | /* |
1876 | * Internal data structure used in gridgen to keep track of |
1877 | * progress. |
1878 | */ |
1879 | struct gridgen_coord { int x, y, r; }; |
1880 | struct gridgen_usage { |
fbd0fc79 |
1881 | int cr; |
1882 | struct block_structure *blocks; |
ab362080 |
1883 | /* grid is a copy of the input grid, modified as we go along */ |
1884 | digit *grid; |
1885 | /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ |
1886 | unsigned char *row; |
1887 | /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ |
1888 | unsigned char *col; |
1889 | /* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */ |
1890 | unsigned char *blk; |
fbd0fc79 |
1891 | /* diag[i*cr+n-1] TRUE if digit n has been placed in diagonal i */ |
1892 | unsigned char *diag; |
ab362080 |
1893 | /* This lists all the empty spaces remaining in the grid. */ |
1894 | struct gridgen_coord *spaces; |
1895 | int nspaces; |
1896 | /* If we need randomisation in the solve, this is our random state. */ |
1897 | random_state *rs; |
1898 | }; |
1899 | |
47f2338e |
1900 | static void gridgen_place(struct gridgen_usage *usage, int x, int y, digit n, |
1901 | int placing) |
1902 | { |
1903 | int cr = usage->cr; |
1904 | usage->row[y*cr+n-1] = usage->col[x*cr+n-1] = |
1905 | usage->blk[usage->blocks->whichblock[y*cr+x]*cr+n-1] = placing; |
1906 | if (usage->diag) { |
1907 | if (ondiag0(y*cr+x)) |
1908 | usage->diag[n-1] = placing; |
1909 | if (ondiag1(y*cr+x)) |
1910 | usage->diag[cr+n-1] = placing; |
1911 | } |
1912 | usage->grid[y*cr+x] = placing ? n : 0; |
1913 | } |
1914 | |
ab362080 |
1915 | /* |
1916 | * The real recursive step in the generating function. |
fbd0fc79 |
1917 | * |
1918 | * Return values: 1 means solution found, 0 means no solution |
1919 | * found on this branch. |
ab362080 |
1920 | */ |
47f2338e |
1921 | static int gridgen_real(struct gridgen_usage *usage, digit *grid, int *steps) |
ab362080 |
1922 | { |
fbd0fc79 |
1923 | int cr = usage->cr; |
ab362080 |
1924 | int i, j, n, sx, sy, bestm, bestr, ret; |
1925 | int *digits; |
1926 | |
1927 | /* |
1928 | * Firstly, check for completion! If there are no spaces left |
1929 | * in the grid, we have a solution. |
1930 | */ |
47f2338e |
1931 | if (usage->nspaces == 0) |
ab362080 |
1932 | return TRUE; |
47f2338e |
1933 | |
1934 | /* |
1935 | * Next, abandon generation if we went over our steps limit. |
1936 | */ |
1937 | if (*steps <= 0) |
1938 | return FALSE; |
1939 | (*steps)--; |
ab362080 |
1940 | |
1941 | /* |
1942 | * Otherwise, there must be at least one space. Find the most |
1943 | * constrained space, using the `r' field as a tie-breaker. |
1944 | */ |
1945 | bestm = cr+1; /* so that any space will beat it */ |
1946 | bestr = 0; |
1947 | i = sx = sy = -1; |
1948 | for (j = 0; j < usage->nspaces; j++) { |
1949 | int x = usage->spaces[j].x, y = usage->spaces[j].y; |
1950 | int m; |
1951 | |
1952 | /* |
1953 | * Find the number of digits that could go in this space. |
1954 | */ |
1955 | m = 0; |
1956 | for (n = 0; n < cr; n++) |
1957 | if (!usage->row[y*cr+n] && !usage->col[x*cr+n] && |
fbd0fc79 |
1958 | !usage->blk[usage->blocks->whichblock[y*cr+x]*cr+n] && |
1959 | (!usage->diag || ((!ondiag0(y*cr+x) || !usage->diag[n]) && |
1960 | (!ondiag1(y*cr+x) || !usage->diag[cr+n])))) |
ab362080 |
1961 | m++; |
1962 | |
1963 | if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) { |
1964 | bestm = m; |
1965 | bestr = usage->spaces[j].r; |
1966 | sx = x; |
1967 | sy = y; |
1968 | i = j; |
1969 | } |
1970 | } |
1971 | |
1972 | /* |
1973 | * Swap that square into the final place in the spaces array, |
1974 | * so that decrementing nspaces will remove it from the list. |
1975 | */ |
1976 | if (i != usage->nspaces-1) { |
1977 | struct gridgen_coord t; |
1978 | t = usage->spaces[usage->nspaces-1]; |
1979 | usage->spaces[usage->nspaces-1] = usage->spaces[i]; |
1980 | usage->spaces[i] = t; |
1981 | } |
1982 | |
1983 | /* |
1984 | * Now we've decided which square to start our recursion at, |
1985 | * simply go through all possible values, shuffling them |
1986 | * randomly first if necessary. |
1987 | */ |
1988 | digits = snewn(bestm, int); |
1989 | j = 0; |
1990 | for (n = 0; n < cr; n++) |
1991 | if (!usage->row[sy*cr+n] && !usage->col[sx*cr+n] && |
fbd0fc79 |
1992 | !usage->blk[usage->blocks->whichblock[sy*cr+sx]*cr+n] && |
1993 | (!usage->diag || ((!ondiag0(sy*cr+sx) || !usage->diag[n]) && |
1994 | (!ondiag1(sy*cr+sx) || !usage->diag[cr+n])))) { |
ab362080 |
1995 | digits[j++] = n+1; |
1996 | } |
1997 | |
947a07d6 |
1998 | if (usage->rs) |
1999 | shuffle(digits, j, sizeof(*digits), usage->rs); |
ab362080 |
2000 | |
2001 | /* And finally, go through the digit list and actually recurse. */ |
2002 | ret = FALSE; |
2003 | for (i = 0; i < j; i++) { |
2004 | n = digits[i]; |
2005 | |
2006 | /* Update the usage structure to reflect the placing of this digit. */ |
47f2338e |
2007 | gridgen_place(usage, sx, sy, n, TRUE); |
ab362080 |
2008 | usage->nspaces--; |
2009 | |
2010 | /* Call the solver recursively. Stop when we find a solution. */ |
47f2338e |
2011 | if (gridgen_real(usage, grid, steps)) { |
ab362080 |
2012 | ret = TRUE; |
47f2338e |
2013 | break; |
2014 | } |
ab362080 |
2015 | |
2016 | /* Revert the usage structure. */ |
47f2338e |
2017 | gridgen_place(usage, sx, sy, n, FALSE); |
ab362080 |
2018 | usage->nspaces++; |
ab362080 |
2019 | } |
2020 | |
2021 | sfree(digits); |
2022 | return ret; |
2023 | } |
2024 | |
2025 | /* |
fbd0fc79 |
2026 | * Entry point to generator. You give it parameters and a starting |
ab362080 |
2027 | * grid, which is simply an array of cr*cr digits. |
2028 | */ |
fbd0fc79 |
2029 | static int gridgen(int cr, struct block_structure *blocks, int xtype, |
47f2338e |
2030 | digit *grid, random_state *rs, int maxsteps) |
ab362080 |
2031 | { |
2032 | struct gridgen_usage *usage; |
fbd0fc79 |
2033 | int x, y, ret; |
ab362080 |
2034 | |
2035 | /* |
2036 | * Clear the grid to start with. |
2037 | */ |
2038 | memset(grid, 0, cr*cr); |
2039 | |
2040 | /* |
2041 | * Create a gridgen_usage structure. |
2042 | */ |
2043 | usage = snew(struct gridgen_usage); |
2044 | |
ab362080 |
2045 | usage->cr = cr; |
fbd0fc79 |
2046 | usage->blocks = blocks; |
ab362080 |
2047 | |
47f2338e |
2048 | usage->grid = grid; |
ab362080 |
2049 | |
2050 | usage->row = snewn(cr * cr, unsigned char); |
2051 | usage->col = snewn(cr * cr, unsigned char); |
2052 | usage->blk = snewn(cr * cr, unsigned char); |
2053 | memset(usage->row, FALSE, cr * cr); |
2054 | memset(usage->col, FALSE, cr * cr); |
2055 | memset(usage->blk, FALSE, cr * cr); |
2056 | |
fbd0fc79 |
2057 | if (xtype) { |
2058 | usage->diag = snewn(2 * cr, unsigned char); |
2059 | memset(usage->diag, FALSE, 2 * cr); |
2060 | } else { |
2061 | usage->diag = NULL; |
2062 | } |
2063 | |
47f2338e |
2064 | /* |
2065 | * Begin by filling in the whole top row with randomly chosen |
2066 | * numbers. This cannot introduce any bias or restriction on |
2067 | * the available grids, since we already know those numbers |
2068 | * are all distinct so all we're doing is choosing their |
2069 | * labels. |
2070 | */ |
2071 | for (x = 0; x < cr; x++) |
2072 | grid[x] = x+1; |
2073 | shuffle(grid, cr, sizeof(*grid), rs); |
2074 | for (x = 0; x < cr; x++) |
2075 | gridgen_place(usage, x, 0, grid[x], TRUE); |
2076 | |
ab362080 |
2077 | usage->spaces = snewn(cr * cr, struct gridgen_coord); |
2078 | usage->nspaces = 0; |
2079 | |
2080 | usage->rs = rs; |
2081 | |
2082 | /* |
47f2338e |
2083 | * Initialise the list of grid spaces, taking care to leave |
2084 | * out the row I've already filled in above. |
ab362080 |
2085 | */ |
47f2338e |
2086 | for (y = 1; y < cr; y++) { |
ab362080 |
2087 | for (x = 0; x < cr; x++) { |
2088 | usage->spaces[usage->nspaces].x = x; |
2089 | usage->spaces[usage->nspaces].y = y; |
2090 | usage->spaces[usage->nspaces].r = random_bits(rs, 31); |
2091 | usage->nspaces++; |
2092 | } |
2093 | } |
2094 | |
2095 | /* |
2096 | * Run the real generator function. |
2097 | */ |
47f2338e |
2098 | ret = gridgen_real(usage, grid, &maxsteps); |
ab362080 |
2099 | |
2100 | /* |
2101 | * Clean up the usage structure now we have our answer. |
2102 | */ |
2103 | sfree(usage->spaces); |
2104 | sfree(usage->blk); |
2105 | sfree(usage->col); |
2106 | sfree(usage->row); |
ab362080 |
2107 | sfree(usage); |
fbd0fc79 |
2108 | |
2109 | return ret; |
ab362080 |
2110 | } |
2111 | |
2112 | /* ---------------------------------------------------------------------- |
2113 | * End of grid generator code. |
1d8e8ad8 |
2114 | */ |
2115 | |
2116 | /* |
2117 | * Check whether a grid contains a valid complete puzzle. |
2118 | */ |
fbd0fc79 |
2119 | static int check_valid(int cr, struct block_structure *blocks, int xtype, |
2120 | digit *grid) |
1d8e8ad8 |
2121 | { |
1d8e8ad8 |
2122 | unsigned char *used; |
fbd0fc79 |
2123 | int x, y, i, j, n; |
1d8e8ad8 |
2124 | |
2125 | used = snewn(cr, unsigned char); |
2126 | |
2127 | /* |
2128 | * Check that each row contains precisely one of everything. |
2129 | */ |
2130 | for (y = 0; y < cr; y++) { |
2131 | memset(used, FALSE, cr); |
2132 | for (x = 0; x < cr; x++) |
2133 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
2134 | used[grid[y*cr+x]-1] = TRUE; |
2135 | for (n = 0; n < cr; n++) |
2136 | if (!used[n]) { |
2137 | sfree(used); |
2138 | return FALSE; |
2139 | } |
2140 | } |
2141 | |
2142 | /* |
2143 | * Check that each column contains precisely one of everything. |
2144 | */ |
2145 | for (x = 0; x < cr; x++) { |
2146 | memset(used, FALSE, cr); |
2147 | for (y = 0; y < cr; y++) |
2148 | if (grid[y*cr+x] > 0 && grid[y*cr+x] <= cr) |
2149 | used[grid[y*cr+x]-1] = TRUE; |
2150 | for (n = 0; n < cr; n++) |
2151 | if (!used[n]) { |
2152 | sfree(used); |
2153 | return FALSE; |
2154 | } |
2155 | } |
2156 | |
2157 | /* |
2158 | * Check that each block contains precisely one of everything. |
2159 | */ |
fbd0fc79 |
2160 | for (i = 0; i < cr; i++) { |
2161 | memset(used, FALSE, cr); |
2162 | for (j = 0; j < cr; j++) |
2163 | if (grid[blocks->blocks[i][j]] > 0 && |
2164 | grid[blocks->blocks[i][j]] <= cr) |
2165 | used[grid[blocks->blocks[i][j]]-1] = TRUE; |
2166 | for (n = 0; n < cr; n++) |
2167 | if (!used[n]) { |
2168 | sfree(used); |
2169 | return FALSE; |
2170 | } |
1d8e8ad8 |
2171 | } |
2172 | |
fbd0fc79 |
2173 | /* |
2174 | * Check that each diagonal contains precisely one of everything. |
2175 | */ |
2176 | if (xtype) { |
2177 | memset(used, FALSE, cr); |
2178 | for (i = 0; i < cr; i++) |
2179 | if (grid[diag0(i)] > 0 && grid[diag0(i)] <= cr) |
2180 | used[grid[diag0(i)]-1] = TRUE; |
2181 | for (n = 0; n < cr; n++) |
2182 | if (!used[n]) { |
2183 | sfree(used); |
2184 | return FALSE; |
2185 | } |
2186 | for (i = 0; i < cr; i++) |
2187 | if (grid[diag1(i)] > 0 && grid[diag1(i)] <= cr) |
2188 | used[grid[diag1(i)]-1] = TRUE; |
2189 | for (n = 0; n < cr; n++) |
2190 | if (!used[n]) { |
2191 | sfree(used); |
2192 | return FALSE; |
2193 | } |
2194 | } |
2195 | |
2196 | sfree(used); |
2197 | return TRUE; |
1d8e8ad8 |
2198 | } |
2199 | |
ef57b17d |
2200 | static int symmetries(game_params *params, int x, int y, int *output, int s) |
2201 | { |
2202 | int c = params->c, r = params->r, cr = c*r; |
2203 | int i = 0; |
2204 | |
154bf9b1 |
2205 | #define ADD(x,y) (*output++ = (x), *output++ = (y), i++) |
2206 | |
2207 | ADD(x, y); |
ef57b17d |
2208 | |
2209 | switch (s) { |
2210 | case SYMM_NONE: |
2211 | break; /* just x,y is all we need */ |
ef57b17d |
2212 | case SYMM_ROT2: |
154bf9b1 |
2213 | ADD(cr - 1 - x, cr - 1 - y); |
2214 | break; |
2215 | case SYMM_ROT4: |
2216 | ADD(cr - 1 - y, x); |
2217 | ADD(y, cr - 1 - x); |
2218 | ADD(cr - 1 - x, cr - 1 - y); |
2219 | break; |
2220 | case SYMM_REF2: |
2221 | ADD(cr - 1 - x, y); |
2222 | break; |
2223 | case SYMM_REF2D: |
2224 | ADD(y, x); |
2225 | break; |
2226 | case SYMM_REF4: |
2227 | ADD(cr - 1 - x, y); |
2228 | ADD(x, cr - 1 - y); |
2229 | ADD(cr - 1 - x, cr - 1 - y); |
2230 | break; |
2231 | case SYMM_REF4D: |
2232 | ADD(y, x); |
2233 | ADD(cr - 1 - x, cr - 1 - y); |
2234 | ADD(cr - 1 - y, cr - 1 - x); |
2235 | break; |
2236 | case SYMM_REF8: |
2237 | ADD(cr - 1 - x, y); |
2238 | ADD(x, cr - 1 - y); |
2239 | ADD(cr - 1 - x, cr - 1 - y); |
2240 | ADD(y, x); |
2241 | ADD(y, cr - 1 - x); |
2242 | ADD(cr - 1 - y, x); |
2243 | ADD(cr - 1 - y, cr - 1 - x); |
2244 | break; |
ef57b17d |
2245 | } |
2246 | |
154bf9b1 |
2247 | #undef ADD |
2248 | |
ef57b17d |
2249 | return i; |
2250 | } |
2251 | |
c566778e |
2252 | static char *encode_solve_move(int cr, digit *grid) |
2253 | { |
2254 | int i, len; |
2255 | char *ret, *p, *sep; |
2256 | |
2257 | /* |
2258 | * It's surprisingly easy to work out _exactly_ how long this |
2259 | * string needs to be. To decimal-encode all the numbers from 1 |
2260 | * to n: |
2261 | * |
2262 | * - every number has a units digit; total is n. |
2263 | * - all numbers above 9 have a tens digit; total is max(n-9,0). |
2264 | * - all numbers above 99 have a hundreds digit; total is max(n-99,0). |
2265 | * - and so on. |
2266 | */ |
2267 | len = 0; |
2268 | for (i = 1; i <= cr; i *= 10) |
2269 | len += max(cr - i + 1, 0); |
2270 | len += cr; /* don't forget the commas */ |
2271 | len *= cr; /* there are cr rows of these */ |
2272 | |
2273 | /* |
2274 | * Now len is one bigger than the total size of the |
2275 | * comma-separated numbers (because we counted an |
2276 | * additional leading comma). We need to have a leading S |
2277 | * and a trailing NUL, so we're off by one in total. |
2278 | */ |
2279 | len++; |
2280 | |
2281 | ret = snewn(len, char); |
2282 | p = ret; |
2283 | *p++ = 'S'; |
2284 | sep = ""; |
2285 | for (i = 0; i < cr*cr; i++) { |
2286 | p += sprintf(p, "%s%d", sep, grid[i]); |
2287 | sep = ","; |
2288 | } |
2289 | *p++ = '\0'; |
2290 | assert(p - ret == len); |
2291 | |
2292 | return ret; |
2293 | } |
3220eba4 |
2294 | |
1185e3c5 |
2295 | static char *new_game_desc(game_params *params, random_state *rs, |
c566778e |
2296 | char **aux, int interactive) |
1d8e8ad8 |
2297 | { |
2298 | int c = params->c, r = params->r, cr = c*r; |
2299 | int area = cr*cr; |
fbd0fc79 |
2300 | struct block_structure *blocks; |
1d8e8ad8 |
2301 | digit *grid, *grid2; |
2302 | struct xy { int x, y; } *locs; |
2303 | int nlocs; |
1185e3c5 |
2304 | char *desc; |
ef57b17d |
2305 | int coords[16], ncoords; |
1af60e1e |
2306 | int maxdiff; |
2307 | int x, y, i, j; |
1d8e8ad8 |
2308 | |
2309 | /* |
7c568a48 |
2310 | * Adjust the maximum difficulty level to be consistent with |
2311 | * the puzzle size: all 2x2 puzzles appear to be Trivial |
2312 | * (DIFF_BLOCK) so we cannot hold out for even a Basic |
2313 | * (DIFF_SIMPLE) one. |
1d8e8ad8 |
2314 | */ |
7c568a48 |
2315 | maxdiff = params->diff; |
2316 | if (c == 2 && r == 2) |
2317 | maxdiff = DIFF_BLOCK; |
1d8e8ad8 |
2318 | |
7c568a48 |
2319 | grid = snewn(area, digit); |
ef57b17d |
2320 | locs = snewn(area, struct xy); |
1d8e8ad8 |
2321 | grid2 = snewn(area, digit); |
1d8e8ad8 |
2322 | |
fbd0fc79 |
2323 | blocks = snew(struct block_structure); |
2324 | blocks->c = params->c; blocks->r = params->r; |
2325 | blocks->whichblock = snewn(area*2, int); |
2326 | blocks->blocks = snewn(cr, int *); |
2327 | for (i = 0; i < cr; i++) |
2328 | blocks->blocks[i] = blocks->whichblock + area + i*cr; |
2329 | #ifdef STANDALONE_SOLVER |
2330 | assert(!"This should never happen, so we don't need to create blocknames"); |
2331 | #endif |
2332 | |
7c568a48 |
2333 | /* |
2334 | * Loop until we get a grid of the required difficulty. This is |
2335 | * nasty, but it seems to be unpleasantly hard to generate |
2336 | * difficult grids otherwise. |
2337 | */ |
fbd0fc79 |
2338 | while (1) { |
7c568a48 |
2339 | /* |
fbd0fc79 |
2340 | * Generate a random solved state, starting by |
2341 | * constructing the block structure. |
7c568a48 |
2342 | */ |
fbd0fc79 |
2343 | if (r == 1) { /* jigsaw mode */ |
2344 | int *dsf = divvy_rectangle(cr, cr, cr, rs); |
2345 | int nb = 0; |
2346 | |
2347 | for (i = 0; i < area; i++) |
2348 | blocks->whichblock[i] = -1; |
2349 | for (i = 0; i < area; i++) { |
2350 | int j = dsf_canonify(dsf, i); |
2351 | if (blocks->whichblock[j] < 0) |
2352 | blocks->whichblock[j] = nb++; |
2353 | blocks->whichblock[i] = blocks->whichblock[j]; |
2354 | } |
2355 | assert(nb == cr); |
2356 | |
2357 | sfree(dsf); |
2358 | } else { /* basic Sudoku mode */ |
2359 | for (y = 0; y < cr; y++) |
2360 | for (x = 0; x < cr; x++) |
2361 | blocks->whichblock[y*cr+x] = (y/c) * c + (x/r); |
2362 | } |
2363 | for (i = 0; i < cr; i++) |
2364 | blocks->blocks[i][cr-1] = 0; |
2365 | for (i = 0; i < area; i++) { |
2366 | int b = blocks->whichblock[i]; |
2367 | j = blocks->blocks[b][cr-1]++; |
2368 | assert(j < cr); |
2369 | blocks->blocks[b][j] = i; |
2370 | } |
2371 | |
47f2338e |
2372 | if (!gridgen(cr, blocks, params->xtype, grid, rs, area*area)) |
2373 | continue; |
fbd0fc79 |
2374 | assert(check_valid(cr, blocks, params->xtype, grid)); |
7c568a48 |
2375 | |
3220eba4 |
2376 | /* |
c566778e |
2377 | * Save the solved grid in aux. |
3220eba4 |
2378 | */ |
2379 | { |
ab53eb64 |
2380 | /* |
2381 | * We might already have written *aux the last time we |
2382 | * went round this loop, in which case we should free |
c566778e |
2383 | * the old aux before overwriting it with the new one. |
ab53eb64 |
2384 | */ |
2385 | if (*aux) { |
ab53eb64 |
2386 | sfree(*aux); |
2387 | } |
c566778e |
2388 | |
2389 | *aux = encode_solve_move(cr, grid); |
3220eba4 |
2390 | } |
2391 | |
7c568a48 |
2392 | /* |
2393 | * Now we have a solved grid, start removing things from it |
2394 | * while preserving solubility. |
2395 | */ |
7c568a48 |
2396 | |
1af60e1e |
2397 | /* |
2398 | * Find the set of equivalence classes of squares permitted |
2399 | * by the selected symmetry. We do this by enumerating all |
2400 | * the grid squares which have no symmetric companion |
2401 | * sorting lower than themselves. |
2402 | */ |
2403 | nlocs = 0; |
2404 | for (y = 0; y < cr; y++) |
2405 | for (x = 0; x < cr; x++) { |
2406 | int i = y*cr+x; |
2407 | int j; |
7c568a48 |
2408 | |
1af60e1e |
2409 | ncoords = symmetries(params, x, y, coords, params->symm); |
2410 | for (j = 0; j < ncoords; j++) |
2411 | if (coords[2*j+1]*cr+coords[2*j] < i) |
2412 | break; |
2413 | if (j == ncoords) { |
154bf9b1 |
2414 | locs[nlocs].x = x; |
2415 | locs[nlocs].y = y; |
2416 | nlocs++; |
2417 | } |
2418 | } |
7c568a48 |
2419 | |
1af60e1e |
2420 | /* |
2421 | * Now shuffle that list. |
2422 | */ |
2423 | shuffle(locs, nlocs, sizeof(*locs), rs); |
de60d8bd |
2424 | |
1af60e1e |
2425 | /* |
2426 | * Now loop over the shuffled list and, for each element, |
2427 | * see whether removing that element (and its reflections) |
2428 | * from the grid will still leave the grid soluble. |
2429 | */ |
2430 | for (i = 0; i < nlocs; i++) { |
2431 | int ret; |
7c568a48 |
2432 | |
1af60e1e |
2433 | x = locs[i].x; |
2434 | y = locs[i].y; |
7c568a48 |
2435 | |
1af60e1e |
2436 | memcpy(grid2, grid, area); |
2437 | ncoords = symmetries(params, x, y, coords, params->symm); |
2438 | for (j = 0; j < ncoords; j++) |
2439 | grid2[coords[2*j+1]*cr+coords[2*j]] = 0; |
7c568a48 |
2440 | |
fbd0fc79 |
2441 | ret = solver(cr, blocks, params->xtype, grid2, maxdiff); |
437ed08c |
2442 | if (ret <= maxdiff) { |
1af60e1e |
2443 | for (j = 0; j < ncoords; j++) |
2444 | grid[coords[2*j+1]*cr+coords[2*j]] = 0; |
7c568a48 |
2445 | } |
2446 | } |
1d8e8ad8 |
2447 | |
7c568a48 |
2448 | memcpy(grid2, grid, area); |
fbd0fc79 |
2449 | |
2450 | if (solver(cr, blocks, params->xtype, grid2, maxdiff) == maxdiff) |
2451 | break; /* found one! */ |
2452 | } |
1d8e8ad8 |
2453 | |
1d8e8ad8 |
2454 | sfree(grid2); |
2455 | sfree(locs); |
2456 | |
1d8e8ad8 |
2457 | /* |
2458 | * Now we have the grid as it will be presented to the user. |
1185e3c5 |
2459 | * Encode it in a game desc. |
1d8e8ad8 |
2460 | */ |
2461 | { |
2462 | char *p; |
2463 | int run, i; |
2464 | |
fbd0fc79 |
2465 | desc = snewn(7 * area, char); |
1185e3c5 |
2466 | p = desc; |
1d8e8ad8 |
2467 | run = 0; |
2468 | for (i = 0; i <= area; i++) { |
2469 | int n = (i < area ? grid[i] : -1); |
2470 | |
2471 | if (!n) |
2472 | run++; |
2473 | else { |
2474 | if (run) { |
2475 | while (run > 0) { |
2476 | int c = 'a' - 1 + run; |
2477 | if (run > 26) |
2478 | c = 'z'; |
2479 | *p++ = c; |
2480 | run -= c - ('a' - 1); |
2481 | } |
2482 | } else { |
2483 | /* |
2484 | * If there's a number in the very top left or |
2485 | * bottom right, there's no point putting an |
2486 | * unnecessary _ before or after it. |
2487 | */ |
1185e3c5 |
2488 | if (p > desc && n > 0) |
1d8e8ad8 |
2489 | *p++ = '_'; |
2490 | } |
2491 | if (n > 0) |
2492 | p += sprintf(p, "%d", n); |
2493 | run = 0; |
2494 | } |
2495 | } |
fbd0fc79 |
2496 | |
2497 | if (r == 1) { |
2498 | int currrun = 0; |
2499 | |
2500 | *p++ = ','; |
2501 | |
2502 | /* |
2503 | * Encode the block structure. We do this by encoding |
2504 | * the pattern of dividing lines: first we iterate |
2505 | * over the cr*(cr-1) internal vertical grid lines in |
2506 | * ordinary reading order, then over the cr*(cr-1) |
2507 | * internal horizontal ones in transposed reading |
2508 | * order. |
2509 | * |
2510 | * We encode the number of non-lines between the |
2511 | * lines; _ means zero (two adjacent divisions), a |
2512 | * means 1, ..., y means 25, and z means 25 non-lines |
2513 | * _and no following line_ (so that za means 26, zb 27 |
2514 | * etc). |
2515 | */ |
2516 | for (i = 0; i <= 2*cr*(cr-1); i++) { |
2517 | int p0, p1, edge; |
2518 | |
2519 | if (i == 2*cr*(cr-1)) { |
2520 | edge = TRUE; /* terminating virtual edge */ |
2521 | } else { |
2522 | if (i < cr*(cr-1)) { |
2523 | y = i/(cr-1); |
2524 | x = i%(cr-1); |
2525 | p0 = y*cr+x; |
2526 | p1 = y*cr+x+1; |
2527 | } else { |
2528 | x = i/(cr-1) - cr; |
2529 | y = i%(cr-1); |
2530 | p0 = y*cr+x; |
2531 | p1 = (y+1)*cr+x; |
2532 | } |
2533 | edge = (blocks->whichblock[p0] != blocks->whichblock[p1]); |
2534 | } |
2535 | |
2536 | if (edge) { |
2537 | while (currrun > 25) |
2538 | *p++ = 'z', currrun -= 25; |
2539 | if (currrun) |
2540 | *p++ = 'a'-1 + currrun; |
2541 | else |
2542 | *p++ = '_'; |
2543 | currrun = 0; |
2544 | } else |
2545 | currrun++; |
2546 | } |
2547 | } |
2548 | |
2549 | assert(p - desc < 7 * area); |
1d8e8ad8 |
2550 | *p++ = '\0'; |
1185e3c5 |
2551 | desc = sresize(desc, p - desc, char); |
1d8e8ad8 |
2552 | } |
2553 | |
2554 | sfree(grid); |
2555 | |
1185e3c5 |
2556 | return desc; |
1d8e8ad8 |
2557 | } |
2558 | |
1185e3c5 |
2559 | static char *validate_desc(game_params *params, char *desc) |
1d8e8ad8 |
2560 | { |
fbd0fc79 |
2561 | int cr = params->c * params->r, area = cr*cr; |
1d8e8ad8 |
2562 | int squares = 0; |
fbd0fc79 |
2563 | int *dsf; |
1d8e8ad8 |
2564 | |
fbd0fc79 |
2565 | while (*desc && *desc != ',') { |
1185e3c5 |
2566 | int n = *desc++; |
1d8e8ad8 |
2567 | if (n >= 'a' && n <= 'z') { |
2568 | squares += n - 'a' + 1; |
2569 | } else if (n == '_') { |
2570 | /* do nothing */; |
2571 | } else if (n > '0' && n <= '9') { |
d0ed57cd |
2572 | int val = atoi(desc-1); |
2573 | if (val < 1 || val > params->c * params->r) |
2574 | return "Out-of-range number in game description"; |
1d8e8ad8 |
2575 | squares++; |
1185e3c5 |
2576 | while (*desc >= '0' && *desc <= '9') |
2577 | desc++; |
1d8e8ad8 |
2578 | } else |
1185e3c5 |
2579 | return "Invalid character in game description"; |
1d8e8ad8 |
2580 | } |
2581 | |
2582 | if (squares < area) |
2583 | return "Not enough data to fill grid"; |
2584 | |
2585 | if (squares > area) |
2586 | return "Too much data to fit in grid"; |
2587 | |
fbd0fc79 |
2588 | if (params->r == 1) { |
1cc153ff |
2589 | int pos; |
2590 | |
fbd0fc79 |
2591 | /* |
2592 | * Now we expect a suffix giving the jigsaw block |
2593 | * structure. Parse it and validate that it divides the |
2594 | * grid into the right number of regions which are the |
2595 | * right size. |
2596 | */ |
2597 | if (*desc != ',') |
2598 | return "Expected jigsaw block structure in game description"; |
1cc153ff |
2599 | pos = 0; |
fbd0fc79 |
2600 | |
2601 | dsf = snew_dsf(area); |
2602 | desc++; |
2603 | |
2604 | while (*desc) { |
2605 | int c, adv; |
2606 | |
2607 | if (*desc == '_') |
2608 | c = 0; |
2609 | else if (*desc >= 'a' && *desc <= 'z') |
2610 | c = *desc - 'a' + 1; |
2611 | else { |
2612 | sfree(dsf); |
2613 | return "Invalid character in game description"; |
2614 | } |
2615 | desc++; |
2616 | |
2617 | adv = (c != 25); /* 'z' is a special case */ |
2618 | |
2619 | while (c-- > 0) { |
2620 | int p0, p1; |
2621 | |
2622 | /* |
2623 | * Non-edge; merge the two dsf classes on either |
2624 | * side of it. |
2625 | */ |
2626 | if (pos >= 2*cr*(cr-1)) { |
2627 | sfree(dsf); |
2628 | return "Too much data in block structure specification"; |
2629 | } else if (pos < cr*(cr-1)) { |
2630 | int y = pos/(cr-1); |
2631 | int x = pos%(cr-1); |
2632 | p0 = y*cr+x; |
2633 | p1 = y*cr+x+1; |
2634 | } else { |
2635 | int x = pos/(cr-1) - cr; |
2636 | int y = pos%(cr-1); |
2637 | p0 = y*cr+x; |
2638 | p1 = (y+1)*cr+x; |
2639 | } |
2640 | dsf_merge(dsf, p0, p1); |
2641 | |
2642 | pos++; |
2643 | } |
2644 | if (adv) |
2645 | pos++; |
2646 | } |
2647 | |
2648 | /* |
2649 | * When desc is exhausted, we expect to have gone exactly |
2650 | * one space _past_ the end of the grid, due to the dummy |
2651 | * edge at the end. |
2652 | */ |
2653 | if (pos != 2*cr*(cr-1)+1) { |
2654 | sfree(dsf); |
2655 | return "Not enough data in block structure specification"; |
2656 | } |
2657 | |
2658 | /* |
2659 | * Now we've got our dsf. Verify that it matches |
2660 | * expectations. |
2661 | */ |
2662 | { |
2663 | int *canons, *counts; |
2664 | int i, j, c, ncanons = 0; |
2665 | |
2666 | canons = snewn(cr, int); |
2667 | counts = snewn(cr, int); |
2668 | |
2669 | for (i = 0; i < area; i++) { |
2670 | j = dsf_canonify(dsf, i); |
2671 | |
2672 | for (c = 0; c < ncanons; c++) |
2673 | if (canons[c] == j) { |
2674 | counts[c]++; |
2675 | if (counts[c] > cr) { |
2676 | sfree(dsf); |
2677 | sfree(canons); |
2678 | sfree(counts); |
2679 | return "A jigsaw block is too big"; |
2680 | } |
2681 | break; |
2682 | } |
2683 | |
2684 | if (c == ncanons) { |
2685 | if (ncanons >= cr) { |
2686 | sfree(dsf); |
2687 | sfree(canons); |
2688 | sfree(counts); |
2689 | return "Too many distinct jigsaw blocks"; |
2690 | } |
2691 | canons[ncanons] = j; |
2692 | counts[ncanons] = 1; |
2693 | ncanons++; |
2694 | } |
2695 | } |
2696 | |
2697 | /* |
2698 | * If we've managed to get through that loop without |
2699 | * tripping either of the error conditions, then we |
2700 | * must have partitioned the entire grid into at most |
2701 | * cr blocks of at most cr squares each; therefore we |
2702 | * must have _exactly_ cr blocks of _exactly_ cr |
2703 | * squares each. I'll verify that by assertion just in |
2704 | * case something has gone horribly wrong, but it |
2705 | * shouldn't have been able to happen by duff input, |
2706 | * only by a bug in the above code. |
2707 | */ |
2708 | assert(ncanons == cr); |
2709 | for (c = 0; c < ncanons; c++) |
2710 | assert(counts[c] == cr); |
2711 | |
2712 | sfree(canons); |
2713 | sfree(counts); |
2714 | } |
2715 | |
2716 | sfree(dsf); |
2717 | } else { |
2718 | if (*desc) |
2719 | return "Unexpected jigsaw block structure in game description"; |
2720 | } |
2721 | |
1d8e8ad8 |
2722 | return NULL; |
2723 | } |
2724 | |
dafd6cf6 |
2725 | static game_state *new_game(midend *me, game_params *params, char *desc) |
1d8e8ad8 |
2726 | { |
2727 | game_state *state = snew(game_state); |
2728 | int c = params->c, r = params->r, cr = c*r, area = cr * cr; |
2729 | int i; |
2730 | |
fbd0fc79 |
2731 | state->cr = cr; |
2732 | state->xtype = params->xtype; |
1d8e8ad8 |
2733 | |
2734 | state->grid = snewn(area, digit); |
c8266e03 |
2735 | state->pencil = snewn(area * cr, unsigned char); |
2736 | memset(state->pencil, 0, area * cr); |
1d8e8ad8 |
2737 | state->immutable = snewn(area, unsigned char); |
2738 | memset(state->immutable, FALSE, area); |
2739 | |
fbd0fc79 |
2740 | state->blocks = snew(struct block_structure); |
2741 | state->blocks->c = c; state->blocks->r = r; |
2742 | state->blocks->refcount = 1; |
2743 | state->blocks->whichblock = snewn(area*2, int); |
2744 | state->blocks->blocks = snewn(cr, int *); |
2745 | for (i = 0; i < cr; i++) |
2746 | state->blocks->blocks[i] = state->blocks->whichblock + area + i*cr; |
2747 | #ifdef STANDALONE_SOLVER |
2748 | state->blocks->blocknames = (char **)smalloc(cr*(sizeof(char *)+80)); |
2749 | #endif |
2750 | |
2ac6d24e |
2751 | state->completed = state->cheated = FALSE; |
1d8e8ad8 |
2752 | |
2753 | i = 0; |
fbd0fc79 |
2754 | while (*desc && *desc != ',') { |
1185e3c5 |
2755 | int n = *desc++; |
1d8e8ad8 |
2756 | if (n >= 'a' && n <= 'z') { |
2757 | int run = n - 'a' + 1; |
2758 | assert(i + run <= area); |
2759 | while (run-- > 0) |
2760 | state->grid[i++] = 0; |
2761 | } else if (n == '_') { |
2762 | /* do nothing */; |
2763 | } else if (n > '0' && n <= '9') { |
2764 | assert(i < area); |
2765 | state->immutable[i] = TRUE; |
1185e3c5 |
2766 | state->grid[i++] = atoi(desc-1); |
2767 | while (*desc >= '0' && *desc <= '9') |
2768 | desc++; |
1d8e8ad8 |
2769 | } else { |
2770 | assert(!"We can't get here"); |
2771 | } |
2772 | } |
2773 | assert(i == area); |
2774 | |
fbd0fc79 |
2775 | if (r == 1) { |
2776 | int pos = 0; |
2777 | int *dsf; |
2778 | int nb; |
2779 | |
2780 | assert(*desc == ','); |
2781 | |
2782 | dsf = snew_dsf(area); |
2783 | desc++; |
2784 | |
2785 | while (*desc) { |
2786 | int c, adv; |
2787 | |
2788 | if (*desc == '_') |
2789 | c = 0; |
2790 | else if (*desc >= 'a' && *desc <= 'z') |
2791 | c = *desc - 'a' + 1; |
2792 | else |
2793 | assert(!"Shouldn't get here"); |
2794 | desc++; |
2795 | |
2796 | adv = (c != 25); /* 'z' is a special case */ |
2797 | |
2798 | while (c-- > 0) { |
2799 | int p0, p1; |
2800 | |
2801 | /* |
2802 | * Non-edge; merge the two dsf classes on either |
2803 | * side of it. |
2804 | */ |
2805 | assert(pos < 2*cr*(cr-1)); |
2806 | if (pos < cr*(cr-1)) { |
2807 | int y = pos/(cr-1); |
2808 | int x = pos%(cr-1); |
2809 | p0 = y*cr+x; |
2810 | p1 = y*cr+x+1; |
2811 | } else { |
2812 | int x = pos/(cr-1) - cr; |
2813 | int y = pos%(cr-1); |
2814 | p0 = y*cr+x; |
2815 | p1 = (y+1)*cr+x; |
2816 | } |
2817 | dsf_merge(dsf, p0, p1); |
2818 | |
2819 | pos++; |
2820 | } |
2821 | if (adv) |
2822 | pos++; |
2823 | } |
2824 | |
2825 | /* |
2826 | * When desc is exhausted, we expect to have gone exactly |
2827 | * one space _past_ the end of the grid, due to the dummy |
2828 | * edge at the end. |
2829 | */ |
2830 | assert(pos == 2*cr*(cr-1)+1); |
2831 | |
2832 | /* |
2833 | * Now we've got our dsf. Translate it into a block |
2834 | * structure. |
2835 | */ |
2836 | nb = 0; |
2837 | for (i = 0; i < area; i++) |
2838 | state->blocks->whichblock[i] = -1; |
2839 | for (i = 0; i < area; i++) { |
2840 | int j = dsf_canonify(dsf, i); |
2841 | if (state->blocks->whichblock[j] < 0) |
2842 | state->blocks->whichblock[j] = nb++; |
2843 | state->blocks->whichblock[i] = state->blocks->whichblock[j]; |
2844 | } |
2845 | assert(nb == cr); |
2846 | |
2847 | sfree(dsf); |
2848 | } else { |
2849 | int x, y; |
2850 | |
2851 | assert(!*desc); |
2852 | |
2853 | for (y = 0; y < cr; y++) |
2854 | for (x = 0; x < cr; x++) |
2855 | state->blocks->whichblock[y*cr+x] = (y/c) * c + (x/r); |
2856 | } |
2857 | |
2858 | /* |
2859 | * Having sorted out whichblock[], set up the block index arrays. |
2860 | */ |
2861 | for (i = 0; i < cr; i++) |
2862 | state->blocks->blocks[i][cr-1] = 0; |
2863 | for (i = 0; i < area; i++) { |
2864 | int b = state->blocks->whichblock[i]; |
2865 | int j = state->blocks->blocks[b][cr-1]++; |
2866 | assert(j < cr); |
2867 | state->blocks->blocks[b][j] = i; |
2868 | } |
2869 | |
2870 | #ifdef STANDALONE_SOLVER |
2871 | /* |
2872 | * Set up the block names for solver diagnostic output. |
2873 | */ |
2874 | { |
2875 | char *p = (char *)(state->blocks->blocknames + cr); |
2876 | |
2877 | if (r == 1) { |
2878 | for (i = 0; i < cr; i++) |
2879 | state->blocks->blocknames[i] = NULL; |
2880 | |
2881 | for (i = 0; i < area; i++) { |
2882 | int j = state->blocks->whichblock[i]; |
2883 | if (!state->blocks->blocknames[j]) { |
2884 | state->blocks->blocknames[j] = p; |
2885 | p += 1 + sprintf(p, "starting at (%d,%d)", |
2886 | 1 + i%cr, 1 + i/cr); |
2887 | } |
2888 | } |
2889 | } else { |
2890 | int bx, by; |
2891 | for (by = 0; by < r; by++) |
2892 | for (bx = 0; bx < c; bx++) { |
2893 | state->blocks->blocknames[by*c+bx] = p; |
2894 | p += 1 + sprintf(p, "(%d,%d)", bx+1, by+1); |
2895 | } |
2896 | } |
2897 | assert(p - (char *)state->blocks->blocknames < cr*(sizeof(char *)+80)); |
2898 | for (i = 0; i < cr; i++) |
2899 | assert(state->blocks->blocknames[i]); |
2900 | } |
2901 | #endif |
2902 | |
1d8e8ad8 |
2903 | return state; |
2904 | } |
2905 | |
2906 | static game_state *dup_game(game_state *state) |
2907 | { |
2908 | game_state *ret = snew(game_state); |
fbd0fc79 |
2909 | int cr = state->cr, area = cr * cr; |
1d8e8ad8 |
2910 | |
fbd0fc79 |
2911 | ret->cr = state->cr; |
2912 | ret->xtype = state->xtype; |
2913 | |
2914 | ret->blocks = state->blocks; |
2915 | ret->blocks->refcount++; |
1d8e8ad8 |
2916 | |
2917 | ret->grid = snewn(area, digit); |
2918 | memcpy(ret->grid, state->grid, area); |
2919 | |
c8266e03 |
2920 | ret->pencil = snewn(area * cr, unsigned char); |
2921 | memcpy(ret->pencil, state->pencil, area * cr); |
2922 | |
1d8e8ad8 |
2923 | ret->immutable = snewn(area, unsigned char); |
2924 | memcpy(ret->immutable, state->immutable, area); |
2925 | |
2926 | ret->completed = state->completed; |
2ac6d24e |
2927 | ret->cheated = state->cheated; |
1d8e8ad8 |
2928 | |
2929 | return ret; |
2930 | } |
2931 | |
2932 | static void free_game(game_state *state) |
2933 | { |
fbd0fc79 |
2934 | if (--state->blocks->refcount == 0) { |
2935 | sfree(state->blocks->whichblock); |
2936 | sfree(state->blocks->blocks); |
2937 | #ifdef STANDALONE_SOLVER |
2938 | sfree(state->blocks->blocknames); |
2939 | #endif |
2940 | sfree(state->blocks); |
2941 | } |
1d8e8ad8 |
2942 | sfree(state->immutable); |
c8266e03 |
2943 | sfree(state->pencil); |
1d8e8ad8 |
2944 | sfree(state->grid); |
2945 | sfree(state); |
2946 | } |
2947 | |
df11cd4e |
2948 | static char *solve_game(game_state *state, game_state *currstate, |
c566778e |
2949 | char *ai, char **error) |
2ac6d24e |
2950 | { |
fbd0fc79 |
2951 | int cr = state->cr; |
c566778e |
2952 | char *ret; |
df11cd4e |
2953 | digit *grid; |
ab362080 |
2954 | int solve_ret; |
2ac6d24e |
2955 | |
3220eba4 |
2956 | /* |
c566778e |
2957 | * If we already have the solution in ai, save ourselves some |
2958 | * time. |
3220eba4 |
2959 | */ |
c566778e |
2960 | if (ai) |
2961 | return dupstr(ai); |
3220eba4 |
2962 | |
c566778e |
2963 | grid = snewn(cr*cr, digit); |
2964 | memcpy(grid, state->grid, cr*cr); |
fbd0fc79 |
2965 | solve_ret = solver(cr, state->blocks, state->xtype, grid, DIFF_RECURSIVE); |
ab362080 |
2966 | |
2967 | *error = NULL; |
df11cd4e |
2968 | |
ab362080 |
2969 | if (solve_ret == DIFF_IMPOSSIBLE) |
2970 | *error = "No solution exists for this puzzle"; |
2971 | else if (solve_ret == DIFF_AMBIGUOUS) |
2972 | *error = "Multiple solutions exist for this puzzle"; |
2973 | |
2974 | if (*error) { |
c566778e |
2975 | sfree(grid); |
c566778e |
2976 | return NULL; |
df11cd4e |
2977 | } |
2978 | |
c566778e |
2979 | ret = encode_solve_move(cr, grid); |
df11cd4e |
2980 | |
c566778e |
2981 | sfree(grid); |
2ac6d24e |
2982 | |
2983 | return ret; |
2984 | } |
2985 | |
fbd0fc79 |
2986 | static char *grid_text_format(int cr, struct block_structure *blocks, |
2987 | int xtype, digit *grid) |
9b4b03d3 |
2988 | { |
fbd0fc79 |
2989 | int vmod, hmod; |
9b4b03d3 |
2990 | int x, y; |
fbd0fc79 |
2991 | int totallen, linelen, nlines; |
2992 | char *ret, *p, ch; |
9b4b03d3 |
2993 | |
2994 | /* |
fbd0fc79 |
2995 | * For non-jigsaw Sudoku, we format in the way we always have, |
2996 | * by having the digits unevenly spaced so that the dividing |
2997 | * lines can fit in: |
2998 | * |
2999 | * . . | . . |
3000 | * . . | . . |
3001 | * ----+---- |
3002 | * . . | . . |
3003 | * . . | . . |
3004 | * |
3005 | * For jigsaw puzzles, however, we must leave space between |
3006 | * _all_ pairs of digits for an optional dividing line, so we |
3007 | * have to move to the rather ugly |
3008 | * |
3009 | * . . . . |
3010 | * ------+------ |
3011 | * . . | . . |
3012 | * +---+ |
3013 | * . . | . | . |
3014 | * ------+ | |
3015 | * . . . | . |
3016 | * |
3017 | * We deal with both cases using the same formatting code; we |
3018 | * simply invent a vmod value such that there's a vertical |
3019 | * dividing line before column i iff i is divisible by vmod |
3020 | * (so it's r in the first case and 1 in the second), and hmod |
3021 | * likewise for horizontal dividing lines. |
9b4b03d3 |
3022 | */ |
9b4b03d3 |
3023 | |
fbd0fc79 |
3024 | if (blocks->r != 1) { |
3025 | vmod = blocks->r; |
3026 | hmod = blocks->c; |
3027 | } else { |
3028 | vmod = hmod = 1; |
3029 | } |
3030 | |
3031 | /* |
3032 | * Line length: we have cr digits, each with a space after it, |
3033 | * and (cr-1)/vmod dividing lines, each with a space after it. |
3034 | * The final space is replaced by a newline, but that doesn't |
3035 | * affect the length. |
3036 | */ |
3037 | linelen = 2*(cr + (cr-1)/vmod); |
3038 | |
3039 | /* |
3040 | * Number of lines: we have cr rows of digits, and (cr-1)/hmod |
3041 | * dividing rows. |
3042 | */ |
3043 | nlines = cr + (cr-1)/hmod; |
3044 | |
3045 | /* |
3046 | * Allocate the space. |
3047 | */ |
3048 | totallen = linelen * nlines; |
3049 | ret = snewn(totallen+1, char); /* leave room for terminating NUL */ |
3050 | |
3051 | /* |
3052 | * Write the text. |
3053 | */ |
3054 | p = ret; |
9b4b03d3 |
3055 | for (y = 0; y < cr; y++) { |
fbd0fc79 |
3056 | /* |
3057 | * Row of digits. |
3058 | */ |
3059 | for (x = 0; x < cr; x++) { |
3060 | /* |
3061 | * Digit. |
3062 | */ |
3063 | digit d = grid[y*cr+x]; |
3064 | |
3065 | if (d == 0) { |
3066 | /* |
3067 | * Empty space: we usually write a dot, but we'll |
3068 | * highlight spaces on the X-diagonals (in X mode) |
3069 | * by using underscores instead. |
3070 | */ |
3071 | if (xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x))) |
3072 | ch = '_'; |
3073 | else |
3074 | ch = '.'; |
3075 | } else if (d <= 9) { |
3076 | ch = '0' + d; |
3077 | } else { |
3078 | ch = 'a' + d-10; |
3079 | } |
3080 | |
3081 | *p++ = ch; |
3082 | if (x == cr-1) { |
3083 | *p++ = '\n'; |
3084 | continue; |
3085 | } |
3086 | *p++ = ' '; |
3087 | |
3088 | if ((x+1) % vmod) |
3089 | continue; |
3090 | |
3091 | /* |
3092 | * Optional dividing line. |
3093 | */ |
3094 | if (blocks->whichblock[y*cr+x] != blocks->whichblock[y*cr+x+1]) |
3095 | ch = '|'; |
3096 | else |
3097 | ch = ' '; |
3098 | *p++ = ch; |
3099 | *p++ = ' '; |
3100 | } |
3101 | if (y == cr-1 || (y+1) % hmod) |
3102 | continue; |
3103 | |
3104 | /* |
3105 | * Dividing row. |
3106 | */ |
3107 | for (x = 0; x < cr; x++) { |
3108 | int dwid; |
3109 | int tl, tr, bl, br; |
3110 | |
3111 | /* |
3112 | * Division between two squares. This varies |
3113 | * complicatedly in length. |
3114 | */ |
3115 | dwid = 2; /* digit and its following space */ |
3116 | if (x == cr-1) |
3117 | dwid--; /* no following space at end of line */ |
3118 | if (x > 0 && x % vmod == 0) |
3119 | dwid++; /* preceding space after a divider */ |
3120 | |
3121 | if (blocks->whichblock[y*cr+x] != blocks->whichblock[(y+1)*cr+x]) |
3122 | ch = '-'; |
3123 | else |
3124 | ch = ' '; |
3125 | |
3126 | while (dwid-- > 0) |
3127 | *p++ = ch; |
3128 | |
3129 | if (x == cr-1) { |
3130 | *p++ = '\n'; |
3131 | break; |
3132 | } |
3133 | |
3134 | if ((x+1) % vmod) |
3135 | continue; |
3136 | |
3137 | /* |
3138 | * Corner square. This is: |
3139 | * - a space if all four surrounding squares are in |
3140 | * the same block |
3141 | * - a vertical line if the two left ones are in one |
3142 | * block and the two right in another |
3143 | * - a horizontal line if the two top ones are in one |
3144 | * block and the two bottom in another |
3145 | * - a plus sign in all other cases. (If we had a |
3146 | * richer character set available we could break |
3147 | * this case up further by doing fun things with |
3148 | * line-drawing T-pieces.) |
3149 | */ |
3150 | tl = blocks->whichblock[y*cr+x]; |
3151 | tr = blocks->whichblock[y*cr+x+1]; |
3152 | bl = blocks->whichblock[(y+1)*cr+x]; |
3153 | br = blocks->whichblock[(y+1)*cr+x+1]; |
3154 | |
3155 | if (tl == tr && tr == bl && bl == br) |
3156 | ch = ' '; |
3157 | else if (tl == bl && tr == br) |
3158 | ch = '|'; |
3159 | else if (tl == tr && bl == br) |
3160 | ch = '-'; |
3161 | else |
3162 | ch = '+'; |
3163 | |
3164 | *p++ = ch; |
3165 | } |
9b4b03d3 |
3166 | } |
3167 | |
fbd0fc79 |
3168 | assert(p - ret == totallen); |
9b4b03d3 |
3169 | *p = '\0'; |
3170 | return ret; |
3171 | } |
3172 | |
3173 | static char *game_text_format(game_state *state) |
3174 | { |
fbd0fc79 |
3175 | return grid_text_format(state->cr, state->blocks, state->xtype, |
3176 | state->grid); |
9b4b03d3 |
3177 | } |
3178 | |
1d8e8ad8 |
3179 | struct game_ui { |
3180 | /* |
3181 | * These are the coordinates of the currently highlighted |
3182 | * square on the grid, or -1,-1 if there isn't one. When there |
3183 | * is, pressing a valid number or letter key or Space will |
3184 | * enter that number or letter in the grid. |
3185 | */ |
3186 | int hx, hy; |
c8266e03 |
3187 | /* |
3188 | * This indicates whether the current highlight is a |
3189 | * pencil-mark one or a real one. |
3190 | */ |
3191 | int hpencil; |
1d8e8ad8 |
3192 | }; |
3193 | |
3194 | static game_ui *new_ui(game_state *state) |
3195 | { |
3196 | game_ui *ui = snew(game_ui); |
3197 | |
3198 | ui->hx = ui->hy = -1; |
c8266e03 |
3199 | ui->hpencil = 0; |
1d8e8ad8 |
3200 | |
3201 | return ui; |
3202 | } |
3203 | |
3204 | static void free_ui(game_ui *ui) |
3205 | { |
3206 | sfree(ui); |
3207 | } |
3208 | |
844f605f |
3209 | static char *encode_ui(game_ui *ui) |
ae8290c6 |
3210 | { |
3211 | return NULL; |
3212 | } |
3213 | |
844f605f |
3214 | static void decode_ui(game_ui *ui, char *encoding) |
ae8290c6 |
3215 | { |
3216 | } |
3217 | |
07dfb697 |
3218 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
3219 | game_state *newstate) |
3220 | { |
fbd0fc79 |
3221 | int cr = newstate->cr; |
07dfb697 |
3222 | /* |
3223 | * We prevent pencil-mode highlighting of a filled square. So |
3224 | * if the user has just filled in a square which we had a |
3225 | * pencil-mode highlight in (by Undo, or by Redo, or by Solve), |
3226 | * then we cancel the highlight. |
3227 | */ |
3228 | if (ui->hx >= 0 && ui->hy >= 0 && ui->hpencil && |
3229 | newstate->grid[ui->hy * cr + ui->hx] != 0) { |
3230 | ui->hx = ui->hy = -1; |
3231 | } |
3232 | } |
3233 | |
1e3e152d |
3234 | struct game_drawstate { |
3235 | int started; |
fbd0fc79 |
3236 | int cr, xtype; |
1e3e152d |
3237 | int tilesize; |
3238 | digit *grid; |
3239 | unsigned char *pencil; |
3240 | unsigned char *hl; |
3241 | /* This is scratch space used within a single call to game_redraw. */ |
3242 | int *entered_items; |
3243 | }; |
3244 | |
df11cd4e |
3245 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
3246 | int x, int y, int button) |
1d8e8ad8 |
3247 | { |
fbd0fc79 |
3248 | int cr = state->cr; |
1d8e8ad8 |
3249 | int tx, ty; |
df11cd4e |
3250 | char buf[80]; |
1d8e8ad8 |
3251 | |
f0ee053c |
3252 | button &= ~MOD_MASK; |
3c833d45 |
3253 | |
ae812854 |
3254 | tx = (x + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
3255 | ty = (y + TILE_SIZE - BORDER) / TILE_SIZE - 1; |
1d8e8ad8 |
3256 | |
39d682c9 |
3257 | if (tx >= 0 && tx < cr && ty >= 0 && ty < cr) { |
3258 | if (button == LEFT_BUTTON) { |
df11cd4e |
3259 | if (state->immutable[ty*cr+tx]) { |
39d682c9 |
3260 | ui->hx = ui->hy = -1; |
3261 | } else if (tx == ui->hx && ty == ui->hy && ui->hpencil == 0) { |
3262 | ui->hx = ui->hy = -1; |
3263 | } else { |
3264 | ui->hx = tx; |
3265 | ui->hy = ty; |
3266 | ui->hpencil = 0; |
3267 | } |
df11cd4e |
3268 | return ""; /* UI activity occurred */ |
39d682c9 |
3269 | } |
3270 | if (button == RIGHT_BUTTON) { |
3271 | /* |
3272 | * Pencil-mode highlighting for non filled squares. |
3273 | */ |
df11cd4e |
3274 | if (state->grid[ty*cr+tx] == 0) { |
39d682c9 |
3275 | if (tx == ui->hx && ty == ui->hy && ui->hpencil) { |
3276 | ui->hx = ui->hy = -1; |
3277 | } else { |
3278 | ui->hpencil = 1; |
3279 | ui->hx = tx; |
3280 | ui->hy = ty; |
3281 | } |
3282 | } else { |
3283 | ui->hx = ui->hy = -1; |
3284 | } |
df11cd4e |
3285 | return ""; /* UI activity occurred */ |
39d682c9 |
3286 | } |
1d8e8ad8 |
3287 | } |
3288 | |
3289 | if (ui->hx != -1 && ui->hy != -1 && |
3290 | ((button >= '1' && button <= '9' && button - '0' <= cr) || |
3291 | (button >= 'a' && button <= 'z' && button - 'a' + 10 <= cr) || |
3292 | (button >= 'A' && button <= 'Z' && button - 'A' + 10 <= cr) || |
0eb4d76e |
3293 | button == ' ' || button == '\010' || button == '\177')) { |
1d8e8ad8 |
3294 | int n = button - '0'; |
3295 | if (button >= 'A' && button <= 'Z') |
3296 | n = button - 'A' + 10; |
3297 | if (button >= 'a' && button <= 'z') |
3298 | n = button - 'a' + 10; |
0eb4d76e |
3299 | if (button == ' ' || button == '\010' || button == '\177') |
1d8e8ad8 |
3300 | n = 0; |
3301 | |
39d682c9 |
3302 | /* |
3303 | * Can't overwrite this square. In principle this shouldn't |
3304 | * happen anyway because we should never have even been |
3305 | * able to highlight the square, but it never hurts to be |
3306 | * careful. |
3307 | */ |
df11cd4e |
3308 | if (state->immutable[ui->hy*cr+ui->hx]) |
39d682c9 |
3309 | return NULL; |
1d8e8ad8 |
3310 | |
c8266e03 |
3311 | /* |
3312 | * Can't make pencil marks in a filled square. In principle |
3313 | * this shouldn't happen anyway because we should never |
3314 | * have even been able to pencil-highlight the square, but |
3315 | * it never hurts to be careful. |
3316 | */ |
df11cd4e |
3317 | if (ui->hpencil && state->grid[ui->hy*cr+ui->hx]) |
c8266e03 |
3318 | return NULL; |
3319 | |
df11cd4e |
3320 | sprintf(buf, "%c%d,%d,%d", |
871bf294 |
3321 | (char)(ui->hpencil && n > 0 ? 'P' : 'R'), ui->hx, ui->hy, n); |
df11cd4e |
3322 | |
3323 | ui->hx = ui->hy = -1; |
3324 | |
3325 | return dupstr(buf); |
3326 | } |
3327 | |
3328 | return NULL; |
3329 | } |
3330 | |
3331 | static game_state *execute_move(game_state *from, char *move) |
3332 | { |
fbd0fc79 |
3333 | int cr = from->cr; |
df11cd4e |
3334 | game_state *ret; |
3335 | int x, y, n; |
3336 | |
3337 | if (move[0] == 'S') { |
3338 | char *p; |
3339 | |
1d8e8ad8 |
3340 | ret = dup_game(from); |
df11cd4e |
3341 | ret->completed = ret->cheated = TRUE; |
3342 | |
3343 | p = move+1; |
3344 | for (n = 0; n < cr*cr; n++) { |
3345 | ret->grid[n] = atoi(p); |
3346 | |
3347 | if (!*p || ret->grid[n] < 1 || ret->grid[n] > cr) { |
3348 | free_game(ret); |
3349 | return NULL; |
3350 | } |
3351 | |
3352 | while (*p && isdigit((unsigned char)*p)) p++; |
3353 | if (*p == ',') p++; |
3354 | } |
3355 | |
3356 | return ret; |
3357 | } else if ((move[0] == 'P' || move[0] == 'R') && |
3358 | sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 && |
3359 | x >= 0 && x < cr && y >= 0 && y < cr && n >= 0 && n <= cr) { |
3360 | |
3361 | ret = dup_game(from); |
3362 | if (move[0] == 'P' && n > 0) { |
3363 | int index = (y*cr+x) * cr + (n-1); |
c8266e03 |
3364 | ret->pencil[index] = !ret->pencil[index]; |
3365 | } else { |
df11cd4e |
3366 | ret->grid[y*cr+x] = n; |
3367 | memset(ret->pencil + (y*cr+x)*cr, 0, cr); |
1d8e8ad8 |
3368 | |
c8266e03 |
3369 | /* |
3370 | * We've made a real change to the grid. Check to see |
3371 | * if the game has been completed. |
3372 | */ |
fbd0fc79 |
3373 | if (!ret->completed && check_valid(cr, ret->blocks, ret->xtype, |
3374 | ret->grid)) { |
c8266e03 |
3375 | ret->completed = TRUE; |
3376 | } |
3377 | } |
df11cd4e |
3378 | return ret; |
3379 | } else |
3380 | return NULL; /* couldn't parse move string */ |
1d8e8ad8 |
3381 | } |
3382 | |
3383 | /* ---------------------------------------------------------------------- |
3384 | * Drawing routines. |
3385 | */ |
3386 | |
1e3e152d |
3387 | #define SIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) |
871bf294 |
3388 | #define GETTILESIZE(cr, w) ( (double)(w-1) / (double)(cr+1) ) |
1d8e8ad8 |
3389 | |
1f3ee4ee |
3390 | static void game_compute_size(game_params *params, int tilesize, |
3391 | int *x, int *y) |
1d8e8ad8 |
3392 | { |
1f3ee4ee |
3393 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
3394 | struct { int tilesize; } ads, *ds = &ads; |
3395 | ads.tilesize = tilesize; |
1e3e152d |
3396 | |
1f3ee4ee |
3397 | *x = SIZE(params->c * params->r); |
3398 | *y = SIZE(params->c * params->r); |
3399 | } |
1d8e8ad8 |
3400 | |
dafd6cf6 |
3401 | static void game_set_size(drawing *dr, game_drawstate *ds, |
3402 | game_params *params, int tilesize) |
1f3ee4ee |
3403 | { |
3404 | ds->tilesize = tilesize; |
1d8e8ad8 |
3405 | } |
3406 | |
8266f3fc |
3407 | static float *game_colours(frontend *fe, int *ncolours) |
1d8e8ad8 |
3408 | { |
3409 | float *ret = snewn(3 * NCOLOURS, float); |
3410 | |
3411 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
3412 | |
fbd0fc79 |
3413 | ret[COL_XDIAGONALS * 3 + 0] = 0.9F * ret[COL_BACKGROUND * 3 + 0]; |
3414 | ret[COL_XDIAGONALS * 3 + 1] = 0.9F * ret[COL_BACKGROUND * 3 + 1]; |
3415 | ret[COL_XDIAGONALS * 3 + 2] = 0.9F * ret[COL_BACKGROUND * 3 + 2]; |
3416 | |
1d8e8ad8 |
3417 | ret[COL_GRID * 3 + 0] = 0.0F; |
3418 | ret[COL_GRID * 3 + 1] = 0.0F; |
3419 | ret[COL_GRID * 3 + 2] = 0.0F; |
3420 | |
3421 | ret[COL_CLUE * 3 + 0] = 0.0F; |
3422 | ret[COL_CLUE * 3 + 1] = 0.0F; |
3423 | ret[COL_CLUE * 3 + 2] = 0.0F; |
3424 | |
3425 | ret[COL_USER * 3 + 0] = 0.0F; |
3426 | ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1]; |
3427 | ret[COL_USER * 3 + 2] = 0.0F; |
3428 | |
fbd0fc79 |
3429 | ret[COL_HIGHLIGHT * 3 + 0] = 0.78F * ret[COL_BACKGROUND * 3 + 0]; |
3430 | ret[COL_HIGHLIGHT * 3 + 1] = 0.78F * ret[COL_BACKGROUND * 3 + 1]; |
3431 | ret[COL_HIGHLIGHT * 3 + 2] = 0.78F * ret[COL_BACKGROUND * 3 + 2]; |
1d8e8ad8 |
3432 | |
7b14a9ec |
3433 | ret[COL_ERROR * 3 + 0] = 1.0F; |
3434 | ret[COL_ERROR * 3 + 1] = 0.0F; |
3435 | ret[COL_ERROR * 3 + 2] = 0.0F; |
3436 | |
c8266e03 |
3437 | ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; |
3438 | ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; |
3439 | ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2]; |
3440 | |
1d8e8ad8 |
3441 | *ncolours = NCOLOURS; |
3442 | return ret; |
3443 | } |
3444 | |
dafd6cf6 |
3445 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
1d8e8ad8 |
3446 | { |
3447 | struct game_drawstate *ds = snew(struct game_drawstate); |
fbd0fc79 |
3448 | int cr = state->cr; |
1d8e8ad8 |
3449 | |
3450 | ds->started = FALSE; |
1d8e8ad8 |
3451 | ds->cr = cr; |
fbd0fc79 |
3452 | ds->xtype = state->xtype; |
1d8e8ad8 |
3453 | ds->grid = snewn(cr*cr, digit); |
fbd0fc79 |
3454 | memset(ds->grid, cr+2, cr*cr); |
c8266e03 |
3455 | ds->pencil = snewn(cr*cr*cr, digit); |
3456 | memset(ds->pencil, 0, cr*cr*cr); |
1d8e8ad8 |
3457 | ds->hl = snewn(cr*cr, unsigned char); |
3458 | memset(ds->hl, 0, cr*cr); |
b71dd7fc |
3459 | ds->entered_items = snewn(cr*cr, int); |
1e3e152d |
3460 | ds->tilesize = 0; /* not decided yet */ |
1d8e8ad8 |
3461 | return ds; |
3462 | } |
3463 | |
dafd6cf6 |
3464 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
1d8e8ad8 |
3465 | { |
3466 | sfree(ds->hl); |
c8266e03 |
3467 | sfree(ds->pencil); |
1d8e8ad8 |
3468 | sfree(ds->grid); |
b71dd7fc |
3469 | sfree(ds->entered_items); |
1d8e8ad8 |
3470 | sfree(ds); |
3471 | } |
3472 | |
dafd6cf6 |
3473 | static void draw_number(drawing *dr, game_drawstate *ds, game_state *state, |
1d8e8ad8 |
3474 | int x, int y, int hl) |
3475 | { |
fbd0fc79 |
3476 | int cr = state->cr; |
1d8e8ad8 |
3477 | int tx, ty; |
3478 | int cx, cy, cw, ch; |
3479 | char str[2]; |
3480 | |
c8266e03 |
3481 | if (ds->grid[y*cr+x] == state->grid[y*cr+x] && |
3482 | ds->hl[y*cr+x] == hl && |
3483 | !memcmp(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr)) |
1d8e8ad8 |
3484 | return; /* no change required */ |
3485 | |
fbd0fc79 |
3486 | tx = BORDER + x * TILE_SIZE + 1 + GRIDEXTRA; |
3487 | ty = BORDER + y * TILE_SIZE + 1 + GRIDEXTRA; |
1d8e8ad8 |
3488 | |
3489 | cx = tx; |
3490 | cy = ty; |
fbd0fc79 |
3491 | cw = TILE_SIZE-1-2*GRIDEXTRA; |
3492 | ch = TILE_SIZE-1-2*GRIDEXTRA; |
3493 | |
3494 | if (x > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x-1]) |
3495 | cx -= GRIDEXTRA, cw += GRIDEXTRA; |
3496 | if (x+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x+1]) |
3497 | cw += GRIDEXTRA; |
3498 | if (y > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y-1)*cr+x]) |
3499 | cy -= GRIDEXTRA, ch += GRIDEXTRA; |
3500 | if (y+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y+1)*cr+x]) |
3501 | ch += GRIDEXTRA; |
1d8e8ad8 |
3502 | |
dafd6cf6 |
3503 | clip(dr, cx, cy, cw, ch); |
1d8e8ad8 |
3504 | |
c8266e03 |
3505 | /* background needs erasing */ |
fbd0fc79 |
3506 | draw_rect(dr, cx, cy, cw, ch, |
3507 | ((hl & 15) == 1 ? COL_HIGHLIGHT : |
3508 | (ds->xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x))) ? COL_XDIAGONALS : |
3509 | COL_BACKGROUND)); |
3510 | |
3511 | /* |
3512 | * Draw the corners of thick lines in corner-adjacent squares, |
3513 | * which jut into this square by one pixel. |
3514 | */ |
3515 | if (x > 0 && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x-1]) |
3516 | draw_rect(dr, tx-GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
3517 | if (x+1 < cr && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x+1]) |
3518 | draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
3519 | if (x > 0 && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x-1]) |
3520 | draw_rect(dr, tx-GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
3521 | if (x+1 < cr && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x+1]) |
3522 | draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID); |
c8266e03 |
3523 | |
3524 | /* pencil-mode highlight */ |
7b14a9ec |
3525 | if ((hl & 15) == 2) { |
c8266e03 |
3526 | int coords[6]; |
3527 | coords[0] = cx; |
3528 | coords[1] = cy; |
3529 | coords[2] = cx+cw/2; |
3530 | coords[3] = cy; |
3531 | coords[4] = cx; |
3532 | coords[5] = cy+ch/2; |
dafd6cf6 |
3533 | draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT); |
c8266e03 |
3534 | } |
1d8e8ad8 |
3535 | |
3536 | /* new number needs drawing? */ |
3537 | if (state->grid[y*cr+x]) { |
3538 | str[1] = '\0'; |
3539 | str[0] = state->grid[y*cr+x] + '0'; |
3540 | if (str[0] > '9') |
3541 | str[0] += 'a' - ('9'+1); |
dafd6cf6 |
3542 | draw_text(dr, tx + TILE_SIZE/2, ty + TILE_SIZE/2, |
1d8e8ad8 |
3543 | FONT_VARIABLE, TILE_SIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE, |
7b14a9ec |
3544 | state->immutable[y*cr+x] ? COL_CLUE : (hl & 16) ? COL_ERROR : COL_USER, str); |
c8266e03 |
3545 | } else { |
edf63745 |
3546 | int i, j, npencil; |
3547 | int pw, ph, pmax, fontsize; |
3548 | |
3549 | /* count the pencil marks required */ |
3550 | for (i = npencil = 0; i < cr; i++) |
3551 | if (state->pencil[(y*cr+x)*cr+i]) |
3552 | npencil++; |
3553 | |
3554 | /* |
3555 | * It's not sensible to arrange pencil marks in the same |
3556 | * layout as the squares within a block, because this leads |
3557 | * to the font being too small. Instead, we arrange pencil |
3558 | * marks in the nearest thing we can to a square layout, |
3559 | * and we adjust the square layout depending on the number |
3560 | * of pencil marks in the square. |
3561 | */ |
3562 | for (pw = 1; pw * pw < npencil; pw++); |
3563 | if (pw < 3) pw = 3; /* otherwise it just looks _silly_ */ |
3564 | ph = (npencil + pw - 1) / pw; |
3565 | if (ph < 2) ph = 2; /* likewise */ |
3566 | pmax = max(pw, ph); |
3567 | fontsize = TILE_SIZE/(pmax*(11-pmax)/8); |
c8266e03 |
3568 | |
3569 | for (i = j = 0; i < cr; i++) |
3570 | if (state->pencil[(y*cr+x)*cr+i]) { |
edf63745 |
3571 | int dx = j % pw, dy = j / pw; |
3572 | |
c8266e03 |
3573 | str[1] = '\0'; |
3574 | str[0] = i + '1'; |
3575 | if (str[0] > '9') |
3576 | str[0] += 'a' - ('9'+1); |
dafd6cf6 |
3577 | draw_text(dr, tx + (4*dx+3) * TILE_SIZE / (4*pw+2), |
edf63745 |
3578 | ty + (4*dy+3) * TILE_SIZE / (4*ph+2), |
3579 | FONT_VARIABLE, fontsize, |
c8266e03 |
3580 | ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str); |
3581 | j++; |
3582 | } |
1d8e8ad8 |
3583 | } |
3584 | |
dafd6cf6 |
3585 | unclip(dr); |
1d8e8ad8 |
3586 | |
dafd6cf6 |
3587 | draw_update(dr, cx, cy, cw, ch); |
1d8e8ad8 |
3588 | |
3589 | ds->grid[y*cr+x] = state->grid[y*cr+x]; |
c8266e03 |
3590 | memcpy(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr); |
1d8e8ad8 |
3591 | ds->hl[y*cr+x] = hl; |
3592 | } |
3593 | |
dafd6cf6 |
3594 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
1d8e8ad8 |
3595 | game_state *state, int dir, game_ui *ui, |
3596 | float animtime, float flashtime) |
3597 | { |
fbd0fc79 |
3598 | int cr = state->cr; |
1d8e8ad8 |
3599 | int x, y; |
3600 | |
3601 | if (!ds->started) { |
3602 | /* |
3603 | * The initial contents of the window are not guaranteed |
3604 | * and can vary with front ends. To be on the safe side, |
3605 | * all games should start by drawing a big |
3606 | * background-colour rectangle covering the whole window. |
3607 | */ |
dafd6cf6 |
3608 | draw_rect(dr, 0, 0, SIZE(cr), SIZE(cr), COL_BACKGROUND); |
1d8e8ad8 |
3609 | |
3610 | /* |
fbd0fc79 |
3611 | * Draw the grid. We draw it as a big thick rectangle of |
3612 | * COL_GRID initially; individual calls to draw_number() |
3613 | * will poke the right-shaped holes in it. |
1d8e8ad8 |
3614 | */ |
fbd0fc79 |
3615 | draw_rect(dr, BORDER-GRIDEXTRA, BORDER-GRIDEXTRA, |
3616 | cr*TILE_SIZE+1+2*GRIDEXTRA, cr*TILE_SIZE+1+2*GRIDEXTRA, |
3617 | COL_GRID); |
1d8e8ad8 |
3618 | } |
3619 | |
3620 | /* |
7b14a9ec |
3621 | * This array is used to keep track of rows, columns and boxes |
3622 | * which contain a number more than once. |
3623 | */ |
3624 | for (x = 0; x < cr * cr; x++) |
b71dd7fc |
3625 | ds->entered_items[x] = 0; |
7b14a9ec |
3626 | for (x = 0; x < cr; x++) |
3627 | for (y = 0; y < cr; y++) { |
3628 | digit d = state->grid[y*cr+x]; |
3629 | if (d) { |
fbd0fc79 |
3630 | int box = state->blocks->whichblock[y*cr+x]; |
3631 | ds->entered_items[x*cr+d-1] |= ((ds->entered_items[x*cr+d-1] & 1) << 1) | 1; |
b71dd7fc |
3632 | ds->entered_items[y*cr+d-1] |= ((ds->entered_items[y*cr+d-1] & 4) << 1) | 4; |
3633 | ds->entered_items[box*cr+d-1] |= ((ds->entered_items[box*cr+d-1] & 16) << 1) | 16; |
fbd0fc79 |
3634 | if (ds->xtype) { |
3635 | if (ondiag0(y*cr+x)) |
3636 | ds->entered_items[d-1] |= ((ds->entered_items[d-1] & 64) << 1) | 64; |
3637 | if (ondiag1(y*cr+x)) |
3638 | ds->entered_items[cr+d-1] |= ((ds->entered_items[cr+d-1] & 64) << 1) | 64; |
3639 | } |
7b14a9ec |
3640 | } |
3641 | } |
3642 | |
3643 | /* |
1d8e8ad8 |
3644 | * Draw any numbers which need redrawing. |
3645 | */ |
3646 | for (x = 0; x < cr; x++) { |
3647 | for (y = 0; y < cr; y++) { |
c8266e03 |
3648 | int highlight = 0; |
7b14a9ec |
3649 | digit d = state->grid[y*cr+x]; |
3650 | |
c8266e03 |
3651 | if (flashtime > 0 && |
3652 | (flashtime <= FLASH_TIME/3 || |
3653 | flashtime >= FLASH_TIME*2/3)) |
3654 | highlight = 1; |
7b14a9ec |
3655 | |
3656 | /* Highlight active input areas. */ |
c8266e03 |
3657 | if (x == ui->hx && y == ui->hy) |
3658 | highlight = ui->hpencil ? 2 : 1; |
7b14a9ec |
3659 | |
3660 | /* Mark obvious errors (ie, numbers which occur more than once |
3661 | * in a single row, column, or box). */ |
5d744557 |
3662 | if (d && ((ds->entered_items[x*cr+d-1] & 2) || |
3663 | (ds->entered_items[y*cr+d-1] & 8) || |
fbd0fc79 |
3664 | (ds->entered_items[state->blocks->whichblock[y*cr+x]*cr+d-1] & 32) || |
3665 | (ds->xtype && ((ondiag0(y*cr+x) && (ds->entered_items[d-1] & 128)) || |
3666 | (ondiag1(y*cr+x) && (ds->entered_items[cr+d-1] & 128)))))) |
7b14a9ec |
3667 | highlight |= 16; |
3668 | |
dafd6cf6 |
3669 | draw_number(dr, ds, state, x, y, highlight); |
1d8e8ad8 |
3670 | } |
3671 | } |
3672 | |
3673 | /* |
3674 | * Update the _entire_ grid if necessary. |
3675 | */ |
3676 | if (!ds->started) { |
dafd6cf6 |
3677 | draw_update(dr, 0, 0, SIZE(cr), SIZE(cr)); |
1d8e8ad8 |
3678 | ds->started = TRUE; |
3679 | } |
3680 | } |
3681 | |
3682 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
e3f21163 |
3683 | int dir, game_ui *ui) |
1d8e8ad8 |
3684 | { |
3685 | return 0.0F; |
3686 | } |
3687 | |
3688 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
e3f21163 |
3689 | int dir, game_ui *ui) |
1d8e8ad8 |
3690 | { |
2ac6d24e |
3691 | if (!oldstate->completed && newstate->completed && |
3692 | !oldstate->cheated && !newstate->cheated) |
1d8e8ad8 |
3693 | return FLASH_TIME; |
3694 | return 0.0F; |
3695 | } |
3696 | |
4d08de49 |
3697 | static int game_timing_state(game_state *state, game_ui *ui) |
48dcdd62 |
3698 | { |
3699 | return TRUE; |
3700 | } |
3701 | |
dafd6cf6 |
3702 | static void game_print_size(game_params *params, float *x, float *y) |
3703 | { |
3704 | int pw, ph; |
3705 | |
3706 | /* |
3707 | * I'll use 9mm squares by default. They should be quite big |
3708 | * for this game, because players will want to jot down no end |
3709 | * of pencil marks in the squares. |
3710 | */ |
3711 | game_compute_size(params, 900, &pw, &ph); |
3712 | *x = pw / 100.0; |
3713 | *y = ph / 100.0; |
3714 | } |
3715 | |
3716 | static void game_print(drawing *dr, game_state *state, int tilesize) |
3717 | { |
fbd0fc79 |
3718 | int cr = state->cr; |
dafd6cf6 |
3719 | int ink = print_mono_colour(dr, 0); |
3720 | int x, y; |
3721 | |
3722 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
3723 | game_drawstate ads, *ds = &ads; |
4413ef0f |
3724 | game_set_size(dr, ds, NULL, tilesize); |
dafd6cf6 |
3725 | |
3726 | /* |
3727 | * Border. |
3728 | */ |
3729 | print_line_width(dr, 3 * TILE_SIZE / 40); |
3730 | draw_rect_outline(dr, BORDER, BORDER, cr*TILE_SIZE, cr*TILE_SIZE, ink); |
3731 | |
3732 | /* |
fbd0fc79 |
3733 | * Highlight X-diagonal squares. |
3734 | */ |
3735 | if (state->xtype) { |
3736 | int i; |
60aa1c74 |
3737 | int xhighlight = print_grey_colour(dr, 0.90F); |
fbd0fc79 |
3738 | |
3739 | for (i = 0; i < cr; i++) |
3740 | draw_rect(dr, BORDER + i*TILE_SIZE, BORDER + i*TILE_SIZE, |
3741 | TILE_SIZE, TILE_SIZE, xhighlight); |
3742 | for (i = 0; i < cr; i++) |
3743 | if (i*2 != cr-1) /* avoid redoing centre square, just for fun */ |
3744 | draw_rect(dr, BORDER + i*TILE_SIZE, |
3745 | BORDER + (cr-1-i)*TILE_SIZE, |
3746 | TILE_SIZE, TILE_SIZE, xhighlight); |
3747 | } |
3748 | |
3749 | /* |
3750 | * Main grid. |
dafd6cf6 |
3751 | */ |
3752 | for (x = 1; x < cr; x++) { |
fbd0fc79 |
3753 | print_line_width(dr, TILE_SIZE / 40); |
dafd6cf6 |
3754 | draw_line(dr, BORDER+x*TILE_SIZE, BORDER, |
3755 | BORDER+x*TILE_SIZE, BORDER+cr*TILE_SIZE, ink); |
3756 | } |
3757 | for (y = 1; y < cr; y++) { |
fbd0fc79 |
3758 | print_line_width(dr, TILE_SIZE / 40); |
dafd6cf6 |
3759 | draw_line(dr, BORDER, BORDER+y*TILE_SIZE, |
3760 | BORDER+cr*TILE_SIZE, BORDER+y*TILE_SIZE, ink); |
3761 | } |
3762 | |
3763 | /* |
fbd0fc79 |
3764 | * Thick lines between cells. In order to do this using the |
3765 | * line-drawing rather than rectangle-drawing API (so as to |
3766 | * get line thicknesses to scale correctly) and yet have |
3767 | * correctly mitred joins between lines, we must do this by |
3768 | * tracing the boundary of each sub-block and drawing it in |
3769 | * one go as a single polygon. |
3770 | */ |
3771 | { |
3772 | int *coords; |
3773 | int bi, i, n; |
3774 | int x, y, dx, dy, sx, sy, sdx, sdy; |
3775 | |
3776 | print_line_width(dr, 3 * TILE_SIZE / 40); |
3777 | |
3778 | /* |
3779 | * Maximum perimeter of a k-omino is 2k+2. (Proof: start |
3780 | * with k unconnected squares, with total perimeter 4k. |
3781 | * Now repeatedly join two disconnected components |
3782 | * together into a larger one; every time you do so you |
3783 | * remove at least two unit edges, and you require k-1 of |
3784 | * these operations to create a single connected piece, so |
3785 | * you must have at most 4k-2(k-1) = 2k+2 unit edges left |
3786 | * afterwards.) |
3787 | */ |
3788 | coords = snewn(4*cr+4, int); /* 2k+2 points, 2 coords per point */ |
3789 | |
3790 | /* |
3791 | * Iterate over all the blocks. |
3792 | */ |
3793 | for (bi = 0; bi < cr; bi++) { |
3794 | |
3795 | /* |
3796 | * For each block, find a starting square within it |
3797 | * which has a boundary at the left. |
3798 | */ |
3799 | for (i = 0; i < cr; i++) { |
3800 | int j = state->blocks->blocks[bi][i]; |
3801 | if (j % cr == 0 || state->blocks->whichblock[j-1] != bi) |
3802 | break; |
3803 | } |
3804 | assert(i < cr); /* every block must have _some_ leftmost square */ |
3805 | x = state->blocks->blocks[bi][i] % cr; |
3806 | y = state->blocks->blocks[bi][i] / cr; |
3807 | dx = -1; |
3808 | dy = 0; |
3809 | |
3810 | /* |
3811 | * Now begin tracing round the perimeter. At all |
3812 | * times, (x,y) describes some square within the |
3813 | * block, and (x+dx,y+dy) is some adjacent square |
3814 | * outside it; so the edge between those two squares |
3815 | * is always an edge of the block. |
3816 | */ |
3817 | sx = x, sy = y, sdx = dx, sdy = dy; /* save starting position */ |
3818 | n = 0; |
3819 | do { |
3820 | int cx, cy, tx, ty, nin; |
3821 | |
3822 | /* |
3823 | * To begin with, record the point at one end of |
3824 | * the edge. To do this, we translate (x,y) down |
3825 | * and right by half a unit (so they're describing |
3826 | * a point in the _centre_ of the square) and then |
3827 | * translate back again in a manner rotated by dy |
3828 | * and dx. |
3829 | */ |
3830 | assert(n < 2*cr+2); |
3831 | cx = ((2*x+1) + dy + dx) / 2; |
3832 | cy = ((2*y+1) - dx + dy) / 2; |
3833 | coords[2*n+0] = BORDER + cx * TILE_SIZE; |
3834 | coords[2*n+1] = BORDER + cy * TILE_SIZE; |
3835 | n++; |
3836 | |
3837 | /* |
3838 | * Now advance to the next edge, by looking at the |
3839 | * two squares beyond it. If they're both outside |
3840 | * the block, we turn right (by leaving x,y the |
3841 | * same and rotating dx,dy clockwise); if they're |
3842 | * both inside, we turn left (by rotating dx,dy |
3843 | * anticlockwise and contriving to leave x+dx,y+dy |
3844 | * unchanged); if one of each, we go straight on |
3845 | * (and may enforce by assertion that they're one |
3846 | * of each the _right_ way round). |
3847 | */ |
3848 | nin = 0; |
3849 | tx = x - dy + dx; |
3850 | ty = y + dx + dy; |
3851 | nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr && |
3852 | state->blocks->whichblock[ty*cr+tx] == bi); |
3853 | tx = x - dy; |
3854 | ty = y + dx; |
3855 | nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr && |
3856 | state->blocks->whichblock[ty*cr+tx] == bi); |
3857 | if (nin == 0) { |
3858 | /* |
3859 | * Turn right. |
3860 | */ |
3861 | int tmp; |
3862 | tmp = dx; |
3863 | dx = -dy; |
3864 | dy = tmp; |
3865 | } else if (nin == 2) { |
3866 | /* |
3867 | * Turn left. |
3868 | */ |
3869 | int tmp; |
3870 | |
3871 | x += dx; |
3872 | y += dy; |
3873 | |
3874 | tmp = dx; |
3875 | dx = dy; |
3876 | dy = -tmp; |
3877 | |
3878 | x -= dx; |
3879 | y -= dy; |
3880 | } else { |
3881 | /* |
3882 | * Go straight on. |
3883 | */ |
3884 | x -= dy; |
3885 | y += dx; |
3886 | } |
3887 | |
3888 | /* |
3889 | * Now enforce by assertion that we ended up |
3890 | * somewhere sensible. |
3891 | */ |
3892 | assert(x >= 0 && x < cr && y >= 0 && y < cr && |
3893 | state->blocks->whichblock[y*cr+x] == bi); |
3894 | assert(x+dx < 0 || x+dx >= cr || y+dy < 0 || y+dy >= cr || |
3895 | state->blocks->whichblock[(y+dy)*cr+(x+dx)] != bi); |
3896 | |
3897 | } while (x != sx || y != sy || dx != sdx || dy != sdy); |
3898 | |
3899 | /* |
3900 | * That's our polygon; now draw it. |
3901 | */ |
3902 | draw_polygon(dr, coords, n, -1, ink); |
3903 | } |
3904 | |
3905 | sfree(coords); |
3906 | } |
3907 | |
3908 | /* |
dafd6cf6 |
3909 | * Numbers. |
3910 | */ |
3911 | for (y = 0; y < cr; y++) |
3912 | for (x = 0; x < cr; x++) |
3913 | if (state->grid[y*cr+x]) { |
3914 | char str[2]; |
3915 | str[1] = '\0'; |
3916 | str[0] = state->grid[y*cr+x] + '0'; |
3917 | if (str[0] > '9') |
3918 | str[0] += 'a' - ('9'+1); |
3919 | draw_text(dr, BORDER + x*TILE_SIZE + TILE_SIZE/2, |
3920 | BORDER + y*TILE_SIZE + TILE_SIZE/2, |
3921 | FONT_VARIABLE, TILE_SIZE/2, |
3922 | ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str); |
3923 | } |
3924 | } |
3925 | |
1d8e8ad8 |
3926 | #ifdef COMBINED |
3927 | #define thegame solo |
3928 | #endif |
3929 | |
3930 | const struct game thegame = { |
750037d7 |
3931 | "Solo", "games.solo", "solo", |
1d8e8ad8 |
3932 | default_params, |
3933 | game_fetch_preset, |
3934 | decode_params, |
3935 | encode_params, |
3936 | free_params, |
3937 | dup_params, |
1d228b10 |
3938 | TRUE, game_configure, custom_params, |
1d8e8ad8 |
3939 | validate_params, |
1185e3c5 |
3940 | new_game_desc, |
1185e3c5 |
3941 | validate_desc, |
1d8e8ad8 |
3942 | new_game, |
3943 | dup_game, |
3944 | free_game, |
2ac6d24e |
3945 | TRUE, solve_game, |
9b4b03d3 |
3946 | TRUE, game_text_format, |
1d8e8ad8 |
3947 | new_ui, |
3948 | free_ui, |
ae8290c6 |
3949 | encode_ui, |
3950 | decode_ui, |
07dfb697 |
3951 | game_changed_state, |
df11cd4e |
3952 | interpret_move, |
3953 | execute_move, |
1f3ee4ee |
3954 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
1d8e8ad8 |
3955 | game_colours, |
3956 | game_new_drawstate, |
3957 | game_free_drawstate, |
3958 | game_redraw, |
3959 | game_anim_length, |
3960 | game_flash_length, |
dafd6cf6 |
3961 | TRUE, FALSE, game_print_size, game_print, |
ac9f41c4 |
3962 | FALSE, /* wants_statusbar */ |
48dcdd62 |
3963 | FALSE, game_timing_state, |
cb0c7d4a |
3964 | REQUIRE_RBUTTON | REQUIRE_NUMPAD, /* flags */ |
1d8e8ad8 |
3965 | }; |
3ddae0ff |
3966 | |
3967 | #ifdef STANDALONE_SOLVER |
3968 | |
3ddae0ff |
3969 | int main(int argc, char **argv) |
3970 | { |
3971 | game_params *p; |
3972 | game_state *s; |
1185e3c5 |
3973 | char *id = NULL, *desc, *err; |
7c568a48 |
3974 | int grade = FALSE; |
ab362080 |
3975 | int ret; |
3ddae0ff |
3976 | |
3977 | while (--argc > 0) { |
3978 | char *p = *++argv; |
ab362080 |
3979 | if (!strcmp(p, "-v")) { |
7c568a48 |
3980 | solver_show_working = TRUE; |
7c568a48 |
3981 | } else if (!strcmp(p, "-g")) { |
3982 | grade = TRUE; |
3ddae0ff |
3983 | } else if (*p == '-') { |
8317499a |
3984 | fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p); |
3ddae0ff |
3985 | return 1; |
3986 | } else { |
3987 | id = p; |
3988 | } |
3989 | } |
3990 | |
3991 | if (!id) { |
ab362080 |
3992 | fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]); |
3ddae0ff |
3993 | return 1; |
3994 | } |
3995 | |
1185e3c5 |
3996 | desc = strchr(id, ':'); |
3997 | if (!desc) { |
3ddae0ff |
3998 | fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); |
3999 | return 1; |
4000 | } |
1185e3c5 |
4001 | *desc++ = '\0'; |
3ddae0ff |
4002 | |
1733f4ca |
4003 | p = default_params(); |
4004 | decode_params(p, id); |
1185e3c5 |
4005 | err = validate_desc(p, desc); |
3ddae0ff |
4006 | if (err) { |
4007 | fprintf(stderr, "%s: %s\n", argv[0], err); |
4008 | return 1; |
4009 | } |
39d682c9 |
4010 | s = new_game(NULL, p, desc); |
3ddae0ff |
4011 | |
fbd0fc79 |
4012 | ret = solver(s->cr, s->blocks, s->xtype, s->grid, DIFF_RECURSIVE); |
ab362080 |
4013 | if (grade) { |
4014 | printf("Difficulty rating: %s\n", |
4015 | ret==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)": |
4016 | ret==DIFF_SIMPLE ? "Basic (row/column/number elimination required)": |
4017 | ret==DIFF_INTERSECT ? "Intermediate (intersectional analysis required)": |
4018 | ret==DIFF_SET ? "Advanced (set elimination required)": |
44bf5f6f |
4019 | ret==DIFF_EXTREME ? "Extreme (complex non-recursive techniques required)": |
ab362080 |
4020 | ret==DIFF_RECURSIVE ? "Unreasonable (guesswork and backtracking required)": |
4021 | ret==DIFF_AMBIGUOUS ? "Ambiguous (multiple solutions exist)": |
4022 | ret==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)": |
4023 | "INTERNAL ERROR: unrecognised difficulty code"); |
3ddae0ff |
4024 | } else { |
fbd0fc79 |
4025 | printf("%s\n", grid_text_format(s->cr, s->blocks, s->xtype, s->grid)); |
3ddae0ff |
4026 | } |
4027 | |
3ddae0ff |
4028 | return 0; |
4029 | } |
4030 | |
4031 | #endif |