X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/puzzles/blobdiff_plain/1d228b10b0f6bbc1fffb5442d2ad934a5e6aaaed..947a07d62de5c0ed1d77f0abdcffe7b6710a2942:/solo.c diff --git a/solo.c b/solo.c index c60cd66..e598fc0 100644 --- a/solo.c +++ b/solo.c @@ -3,6 +3,30 @@ * * TODO: * + * - reports from users are that `Trivial'-mode puzzles are still + * rather hard compared to newspapers' easy ones, so some better + * low-end difficulty grading would be nice + * + it's possible that really easy puzzles always have + * _several_ things you can do, so don't make you hunt too + * hard for the one deduction you can currently make + * + it's also possible that easy puzzles require fewer + * cross-eliminations: perhaps there's a higher incidence of + * things you can deduce by looking only at (say) rows, + * rather than things you have to check both rows and columns + * for + * + but really, what I need to do is find some really easy + * puzzles and _play_ them, to see what's actually easy about + * them + * + while I'm revamping this area, filling in the _last_ + * number in a nearly-full row or column should certainly be + * permitted even at the lowest difficulty level. + * + also Owen noticed that `Basic' grids requiring numeric + * elimination are actually very hard, so I wonder if a + * difficulty gradation between that and positional- + * elimination-only might be in order + * + but it's not good to have _too_ many difficulty levels, or + * it'll take too long to randomly generate a given level. + * * - it might still be nice to do some prioritisation on the * removal of numbers from the grid * + one possibility is to try to minimise the maximum number @@ -20,8 +44,13 @@ * click, _or_ you highlight a square and then type. At most * one thing is ever highlighted at a time, so there's no way * to confuse the two. - * + `pencil marks' might be useful for more subtle forms of - * deduction, now we can create puzzles that require them. + * + then again, I don't actually like sudoku.com's interface; + * it's too much like a paint package whereas I prefer to + * think of Solo as a text editor. + * + another PDA-friendly possibility is a drag interface: + * _drag_ numbers from the palette into the grid squares. + * Thought experiments suggest I'd prefer that to the + * sudoku.com approach, but I haven't actually tried it. */ /* @@ -62,13 +91,11 @@ #ifdef STANDALONE_SOLVER #include -int solver_show_working; +int solver_show_working, solver_recurse_depth; #endif #include "puzzles.h" -#define max(x,y) ((x)>(y)?(x):(y)) - /* * To save space, I store digits internally as unsigned char. This * imposes a hard limit of 255 on the order of the puzzle. Since @@ -80,12 +107,14 @@ int solver_show_working; typedef unsigned char digit; #define ORDER_MAX 255 -#define TILE_SIZE 32 -#define BORDER 18 +#define PREFERRED_TILE_SIZE 32 +#define TILE_SIZE (ds->tilesize) +#define BORDER (TILE_SIZE / 2) #define FLASH_TIME 0.4F -enum { SYMM_NONE, SYMM_ROT2, SYMM_ROT4, SYMM_REF4 }; +enum { SYMM_NONE, SYMM_ROT2, SYMM_ROT4, SYMM_REF2, SYMM_REF2D, SYMM_REF4, + SYMM_REF4D, SYMM_REF8 }; enum { DIFF_BLOCK, DIFF_SIMPLE, DIFF_INTERSECT, DIFF_SET, DIFF_RECURSIVE, DIFF_AMBIGUOUS, DIFF_IMPOSSIBLE }; @@ -96,6 +125,8 @@ enum { COL_CLUE, COL_USER, COL_HIGHLIGHT, + COL_ERROR, + COL_PENCIL, NCOLOURS }; @@ -106,8 +137,9 @@ struct game_params { struct game_state { int c, r; digit *grid; + unsigned char *pencil; /* c*r*c*r elements */ unsigned char *immutable; /* marks which digits are clues */ - int completed; + int completed, cheated; }; static game_params *default_params(void) @@ -116,7 +148,7 @@ static game_params *default_params(void) ret->c = ret->r = 3; ret->symm = SYMM_ROT2; /* a plausible default */ - ret->diff = DIFF_SIMPLE; /* so is this */ + ret->diff = DIFF_BLOCK; /* so is this */ return ret; } @@ -141,11 +173,15 @@ static int game_fetch_preset(int i, char **name, game_params **params) } presets[] = { { "2x2 Trivial", { 2, 2, SYMM_ROT2, DIFF_BLOCK } }, { "2x3 Basic", { 2, 3, SYMM_ROT2, DIFF_SIMPLE } }, + { "3x3 Trivial", { 3, 3, SYMM_ROT2, DIFF_BLOCK } }, { "3x3 Basic", { 3, 3, SYMM_ROT2, DIFF_SIMPLE } }, { "3x3 Intermediate", { 3, 3, SYMM_ROT2, DIFF_INTERSECT } }, { "3x3 Advanced", { 3, 3, SYMM_ROT2, DIFF_SET } }, + { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE } }, +#ifndef SLOW_SYSTEM { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE } }, { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE } }, +#endif }; if (i < 0 || i >= lenof(presets)) @@ -157,12 +193,9 @@ static int game_fetch_preset(int i, char **name, game_params **params) return TRUE; } -static game_params *decode_params(char const *string) +static void decode_params(game_params *ret, char const *string) { - game_params *ret = default_params(); - ret->c = ret->r = atoi(string); - ret->symm = SYMM_ROT2; while (*string && isdigit((unsigned char)*string)) string++; if (*string == 'x') { string++; @@ -171,12 +204,22 @@ static game_params *decode_params(char const *string) } while (*string) { if (*string == 'r' || *string == 'm' || *string == 'a') { - int sn, sc; + int sn, sc, sd; sc = *string++; + if (*string == 'd') { + sd = TRUE; + string++; + } else { + sd = FALSE; + } sn = atoi(string); while (*string && isdigit((unsigned char)*string)) string++; + if (sc == 'm' && sn == 8) + ret->symm = SYMM_REF8; if (sc == 'm' && sn == 4) - ret->symm = SYMM_REF4; + ret->symm = sd ? SYMM_REF4D : SYMM_REF4; + if (sc == 'm' && sn == 2) + ret->symm = sd ? SYMM_REF2D : SYMM_REF2; if (sc == 'r' && sn == 4) ret->symm = SYMM_ROT4; if (sc == 'r' && sn == 2) @@ -193,23 +236,37 @@ static game_params *decode_params(char const *string) string++, ret->diff = DIFF_INTERSECT; else if (*string == 'a') /* advanced */ string++, ret->diff = DIFF_SET; + else if (*string == 'u') /* unreasonable */ + string++, ret->diff = DIFF_RECURSIVE; } else string++; /* eat unknown character */ } - - return ret; } -static char *encode_params(game_params *params) +static char *encode_params(game_params *params, int full) { char str[80]; - /* - * Symmetry is a game generation preference and hence is left - * out of the encoding. Users can add it back in as they see - * fit. - */ sprintf(str, "%dx%d", params->c, params->r); + if (full) { + switch (params->symm) { + case SYMM_REF8: strcat(str, "m8"); break; + case SYMM_REF4: strcat(str, "m4"); break; + case SYMM_REF4D: strcat(str, "md4"); break; + case SYMM_REF2: strcat(str, "m2"); break; + case SYMM_REF2D: strcat(str, "md2"); break; + case SYMM_ROT4: strcat(str, "r4"); break; + /* case SYMM_ROT2: strcat(str, "r2"); break; [default] */ + case SYMM_NONE: strcat(str, "a"); break; + } + switch (params->diff) { + /* case DIFF_BLOCK: strcat(str, "dt"); break; [default] */ + case DIFF_SIMPLE: strcat(str, "db"); break; + case DIFF_INTERSECT: strcat(str, "di"); break; + case DIFF_SET: strcat(str, "da"); break; + case DIFF_RECURSIVE: strcat(str, "du"); break; + } + } return dupstr(str); } @@ -234,12 +291,14 @@ static config_item *game_configure(game_params *params) ret[2].name = "Symmetry"; ret[2].type = C_CHOICES; - ret[2].sval = ":None:2-way rotation:4-way rotation:4-way mirror"; + ret[2].sval = ":None:2-way rotation:4-way rotation:2-way mirror:" + "2-way diagonal mirror:4-way mirror:4-way diagonal mirror:" + "8-way mirror"; ret[2].ival = params->symm; ret[3].name = "Difficulty"; ret[3].type = C_CHOICES; - ret[3].sval = ":Trivial:Basic:Intermediate:Advanced"; + ret[3].sval = ":Trivial:Basic:Intermediate:Advanced:Unreasonable"; ret[3].ival = params->diff; ret[4].name = NULL; @@ -262,7 +321,7 @@ static game_params *custom_params(config_item *cfg) return ret; } -static char *validate_params(game_params *params) +static char *validate_params(game_params *params, int full) { if (params->c < 2 || params->r < 2) return "Both dimensions must be at least 2"; @@ -272,276 +331,16 @@ static char *validate_params(game_params *params) } /* ---------------------------------------------------------------------- - * Full recursive Solo solver. - * - * The algorithm for this solver is shamelessly copied from a - * Python solver written by Andrew Wilkinson (which is GPLed, but - * I've reused only ideas and no code). It mostly just does the - * obvious recursive thing: pick an empty square, put one of the - * possible digits in it, recurse until all squares are filled, - * backtrack and change some choices if necessary. - * - * The clever bit is that every time it chooses which square to - * fill in next, it does so by counting the number of _possible_ - * numbers that can go in each square, and it prioritises so that - * it picks a square with the _lowest_ number of possibilities. The - * idea is that filling in lots of the obvious bits (particularly - * any squares with only one possibility) will cut down on the list - * of possibilities for other squares and hence reduce the enormous - * search space as much as possible as early as possible. - * - * In practice the algorithm appeared to work very well; run on - * sample problems from the Times it completed in well under a - * second on my G5 even when written in Python, and given an empty - * grid (so that in principle it would enumerate _all_ solved - * grids!) it found the first valid solution just as quickly. So - * with a bit more randomisation I see no reason not to use this as - * my grid generator. - */ - -/* - * Internal data structure used in solver to keep track of - * progress. - */ -struct rsolve_coord { int x, y, r; }; -struct rsolve_usage { - int c, r, cr; /* cr == c*r */ - /* grid is a copy of the input grid, modified as we go along */ - digit *grid; - /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ - unsigned char *row; - /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ - unsigned char *col; - /* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */ - unsigned char *blk; - /* This lists all the empty spaces remaining in the grid. */ - struct rsolve_coord *spaces; - int nspaces; - /* If we need randomisation in the solve, this is our random state. */ - random_state *rs; - /* Number of solutions so far found, and maximum number we care about. */ - int solns, maxsolns; -}; - -/* - * The real recursive step in the solving function. - */ -static void rsolve_real(struct rsolve_usage *usage, digit *grid) -{ - int c = usage->c, r = usage->r, cr = usage->cr; - int i, j, n, sx, sy, bestm, bestr; - int *digits; - - /* - * Firstly, check for completion! If there are no spaces left - * in the grid, we have a solution. - */ - if (usage->nspaces == 0) { - if (!usage->solns) { - /* - * This is our first solution, so fill in the output grid. - */ - memcpy(grid, usage->grid, cr * cr); - } - usage->solns++; - return; - } - - /* - * Otherwise, there must be at least one space. Find the most - * constrained space, using the `r' field as a tie-breaker. - */ - bestm = cr+1; /* so that any space will beat it */ - bestr = 0; - i = sx = sy = -1; - for (j = 0; j < usage->nspaces; j++) { - int x = usage->spaces[j].x, y = usage->spaces[j].y; - int m; - - /* - * Find the number of digits that could go in this space. - */ - m = 0; - for (n = 0; n < cr; n++) - if (!usage->row[y*cr+n] && !usage->col[x*cr+n] && - !usage->blk[((y/c)*c+(x/r))*cr+n]) - m++; - - if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) { - bestm = m; - bestr = usage->spaces[j].r; - sx = x; - sy = y; - i = j; - } - } - - /* - * Swap that square into the final place in the spaces array, - * so that decrementing nspaces will remove it from the list. - */ - if (i != usage->nspaces-1) { - struct rsolve_coord t; - t = usage->spaces[usage->nspaces-1]; - usage->spaces[usage->nspaces-1] = usage->spaces[i]; - usage->spaces[i] = t; - } - - /* - * Now we've decided which square to start our recursion at, - * simply go through all possible values, shuffling them - * randomly first if necessary. - */ - digits = snewn(bestm, int); - j = 0; - for (n = 0; n < cr; n++) - if (!usage->row[sy*cr+n] && !usage->col[sx*cr+n] && - !usage->blk[((sy/c)*c+(sx/r))*cr+n]) { - digits[j++] = n+1; - } - - if (usage->rs) { - /* shuffle */ - for (i = j; i > 1; i--) { - int p = random_upto(usage->rs, i); - if (p != i-1) { - int t = digits[p]; - digits[p] = digits[i-1]; - digits[i-1] = t; - } - } - } - - /* And finally, go through the digit list and actually recurse. */ - for (i = 0; i < j; i++) { - n = digits[i]; - - /* Update the usage structure to reflect the placing of this digit. */ - usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = - usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = TRUE; - usage->grid[sy*cr+sx] = n; - usage->nspaces--; - - /* Call the solver recursively. */ - rsolve_real(usage, grid); - - /* - * If we have seen as many solutions as we need, terminate - * all processing immediately. - */ - if (usage->solns >= usage->maxsolns) - break; - - /* Revert the usage structure. */ - usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = - usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = FALSE; - usage->grid[sy*cr+sx] = 0; - usage->nspaces++; - } - - sfree(digits); -} - -/* - * Entry point to solver. You give it dimensions and a starting - * grid, which is simply an array of N^4 digits. In that array, 0 - * means an empty square, and 1..N mean a clue square. - * - * Return value is the number of solutions found; searching will - * stop after the provided `max'. (Thus, you can pass max==1 to - * indicate that you only care about finding _one_ solution, or - * max==2 to indicate that you want to know the difference between - * a unique and non-unique solution.) The input parameter `grid' is - * also filled in with the _first_ (or only) solution found by the - * solver. - */ -static int rsolve(int c, int r, digit *grid, random_state *rs, int max) -{ - struct rsolve_usage *usage; - int x, y, cr = c*r; - int ret; - - /* - * Create an rsolve_usage structure. - */ - usage = snew(struct rsolve_usage); - - usage->c = c; - usage->r = r; - usage->cr = cr; - - usage->grid = snewn(cr * cr, digit); - memcpy(usage->grid, grid, cr * cr); - - usage->row = snewn(cr * cr, unsigned char); - usage->col = snewn(cr * cr, unsigned char); - usage->blk = snewn(cr * cr, unsigned char); - memset(usage->row, FALSE, cr * cr); - memset(usage->col, FALSE, cr * cr); - memset(usage->blk, FALSE, cr * cr); - - usage->spaces = snewn(cr * cr, struct rsolve_coord); - usage->nspaces = 0; - - usage->solns = 0; - usage->maxsolns = max; - - usage->rs = rs; - - /* - * Now fill it in with data from the input grid. - */ - for (y = 0; y < cr; y++) { - for (x = 0; x < cr; x++) { - int v = grid[y*cr+x]; - if (v == 0) { - usage->spaces[usage->nspaces].x = x; - usage->spaces[usage->nspaces].y = y; - if (rs) - usage->spaces[usage->nspaces].r = random_bits(rs, 31); - else - usage->spaces[usage->nspaces].r = usage->nspaces; - usage->nspaces++; - } else { - usage->row[y*cr+v-1] = TRUE; - usage->col[x*cr+v-1] = TRUE; - usage->blk[((y/c)*c+(x/r))*cr+v-1] = TRUE; - } - } - } - - /* - * Run the real recursive solving function. - */ - rsolve_real(usage, grid); - ret = usage->solns; - - /* - * Clean up the usage structure now we have our answer. - */ - sfree(usage->spaces); - sfree(usage->blk); - sfree(usage->col); - sfree(usage->row); - sfree(usage->grid); - sfree(usage); - - /* - * And return. - */ - return ret; -} - -/* ---------------------------------------------------------------------- - * End of recursive solver code. - */ - -/* ---------------------------------------------------------------------- - * Less capable non-recursive solver. This one is used to check - * solubility of a grid as we gradually remove numbers from it: by - * verifying a grid using this solver we can ensure it isn't _too_ - * hard (e.g. does not actually require guessing and backtracking). - * + * Solver. + * + * This solver is used for several purposes: + * + to generate filled grids as the basis for new puzzles (by + * supplying no clue squares at all) + * + to check solubility of a grid as we gradually remove numbers + * from it + * + to solve an externally generated puzzle when the user selects + * `Solve'. + * * It supports a variety of specific modes of reasoning. By * enabling or disabling subsets of these modes we can arrange a * range of difficulty levels. @@ -587,6 +386,11 @@ static int rsolve(int c, int r, digit *grid, random_state *rs, int max) * places, found by taking the _complement_ of the union of * the numbers' possible positions (or the spaces' possible * contents). + * + * - Recursion. If all else fails, we pick one of the currently + * most constrained empty squares and take a random guess at its + * contents, then continue solving on that basis and see if we + * get any further. */ /* @@ -605,7 +409,7 @@ static int rsolve(int c, int r, digit *grid, random_state *rs, int max) #define YTRANS(y) (((y)%c)*r+(y)/c) #define YUNTRANS(y) (((y)%r)*c+(y)/r) -struct nsolve_usage { +struct solver_usage { int c, r, cr; /* * We set up a cubic array, indexed by x, y and digit; each @@ -641,7 +445,7 @@ struct nsolve_usage { * a particular number in it. The y-coordinate passed in here is * transformed. */ -static void nsolve_place(struct nsolve_usage *usage, int x, int y, int n) +static void solver_place(struct solver_usage *usage, int x, int y, int n) { int c = usage->c, r = usage->r, cr = usage->cr; int i, j, bx, by; @@ -692,7 +496,7 @@ static void nsolve_place(struct nsolve_usage *usage, int x, int y, int n) usage->blk[((y%r)*c+(x/r))*cr+n-1] = TRUE; } -static int nsolve_elim(struct nsolve_usage *usage, int start, int step +static int solver_elim(struct solver_usage *usage, int start, int step #ifdef STANDALONE_SOLVER , char *fmt, ... #endif @@ -726,22 +530,36 @@ static int nsolve_elim(struct nsolve_usage *usage, int start, int step #ifdef STANDALONE_SOLVER if (solver_show_working) { va_list ap; + printf("%*s", solver_recurse_depth*4, ""); va_start(ap, fmt); vprintf(fmt, ap); va_end(ap); - printf(":\n placing %d at (%d,%d)\n", - n, 1+x, 1+YUNTRANS(y)); + printf(":\n%*s placing %d at (%d,%d)\n", + solver_recurse_depth*4, "", n, 1+x, 1+YUNTRANS(y)); } #endif - nsolve_place(usage, x, y, n); - return TRUE; + solver_place(usage, x, y, n); + return +1; } + } else if (m == 0) { +#ifdef STANDALONE_SOLVER + if (solver_show_working) { + va_list ap; + printf("%*s", solver_recurse_depth*4, ""); + va_start(ap, fmt); + vprintf(fmt, ap); + va_end(ap); + printf(":\n%*s no possibilities available\n", + solver_recurse_depth*4, ""); + } +#endif + return -1; } - return FALSE; + return 0; } -static int nsolve_intersect(struct nsolve_usage *usage, +static int solver_intersect(struct solver_usage *usage, int start1, int step1, int start2, int step2 #ifdef STANDALONE_SOLVER , char *fmt, ... @@ -760,16 +578,16 @@ static int nsolve_intersect(struct nsolve_usage *usage, if (usage->cube[p] && !(p >= start2 && p < start2+cr*step2 && (p - start2) % step2 == 0)) - return FALSE; /* there is, so we can't deduce */ + return 0; /* there is, so we can't deduce */ } /* * We have determined that all set bits in the first domain are * within its overlap with the second. So loop over the second * domain and remove all set bits that aren't also in that - * overlap; return TRUE iff we actually _did_ anything. + * overlap; return +1 iff we actually _did_ anything. */ - ret = FALSE; + ret = 0; for (i = 0; i < cr; i++) { int p = start2+i*step2; if (usage->cube[p] && @@ -781,6 +599,7 @@ static int nsolve_intersect(struct nsolve_usage *usage, if (!ret) { va_list ap; + printf("%*s", solver_recurse_depth*4, ""); va_start(ap, fmt); vprintf(fmt, ap); va_end(ap); @@ -792,11 +611,11 @@ static int nsolve_intersect(struct nsolve_usage *usage, px = py / cr; py %= cr; - printf(" ruling out %d at (%d,%d)\n", - pn, 1+px, 1+YUNTRANS(py)); + printf("%*s ruling out %d at (%d,%d)\n", + solver_recurse_depth*4, "", pn, 1+px, 1+YUNTRANS(py)); } #endif - ret = TRUE; /* we did something */ + ret = +1; /* we did something */ usage->cube[p] = 0; } } @@ -804,7 +623,12 @@ static int nsolve_intersect(struct nsolve_usage *usage, return ret; } -static int nsolve_set(struct nsolve_usage *usage, +struct solver_scratch { + unsigned char *grid, *rowidx, *colidx, *set; +}; + +static int solver_set(struct solver_usage *usage, + struct solver_scratch *scratch, int start, int step1, int step2 #ifdef STANDALONE_SOLVER , char *fmt, ... @@ -813,10 +637,10 @@ static int nsolve_set(struct nsolve_usage *usage, { int c = usage->c, r = usage->r, cr = c*r; int i, j, n, count; - unsigned char *grid = snewn(cr*cr, unsigned char); - unsigned char *rowidx = snewn(cr, unsigned char); - unsigned char *colidx = snewn(cr, unsigned char); - unsigned char *set = snewn(cr, unsigned char); + unsigned char *grid = scratch->grid; + unsigned char *rowidx = scratch->rowidx; + unsigned char *colidx = scratch->colidx; + unsigned char *set = scratch->set; /* * We are passed a cr-by-cr matrix of booleans. Our first job @@ -831,14 +655,15 @@ static int nsolve_set(struct nsolve_usage *usage, for (j = 0; j < cr; j++) if (usage->cube[start+i*step1+j*step2]) first = j, count++; - if (count == 0) { - /* - * This condition actually marks a completely insoluble - * (i.e. internally inconsistent) puzzle. We return and - * report no progress made. - */ - return FALSE; - } + + /* + * If count == 0, then there's a row with no 1s at all and + * the puzzle is internally inconsistent. However, we ought + * to have caught this already during the simpler reasoning + * methods, so we can safely fail an assertion if we reach + * this point here. + */ + assert(count > 0); if (count == 1) rowidx[i] = colidx[first] = FALSE; } @@ -904,7 +729,22 @@ static int nsolve_set(struct nsolve_usage *usage, * indicates a faulty deduction before this point or * even a bogus clue. */ - assert(rows <= n - count); + if (rows > n - count) { +#ifdef STANDALONE_SOLVER + if (solver_show_working) { + va_list ap; + printf("%*s", solver_recurse_depth*4, + ""); + va_start(ap, fmt); + vprintf(fmt, ap); + va_end(ap); + printf(":\n%*s contradiction reached\n", + solver_recurse_depth*4, ""); + } +#endif + return -1; + } + if (rows >= n - count) { int progress = FALSE; @@ -912,8 +752,8 @@ static int nsolve_set(struct nsolve_usage *usage, * We've got one! Now, for each row which _doesn't_ * satisfy the criterion, eliminate all its set * bits in the positions _not_ listed in `set'. - * Return TRUE (meaning progress has been made) if - * we successfully eliminated anything at all. + * Return +1 (meaning progress has been made) if we + * successfully eliminated anything at all. * * This involves referring back through * rowidx/colidx in order to work out which actual @@ -934,9 +774,11 @@ static int nsolve_set(struct nsolve_usage *usage, #ifdef STANDALONE_SOLVER if (solver_show_working) { int px, py, pn; - + if (!progress) { va_list ap; + printf("%*s", solver_recurse_depth*4, + ""); va_start(ap, fmt); vprintf(fmt, ap); va_end(ap); @@ -948,7 +790,8 @@ static int nsolve_set(struct nsolve_usage *usage, px = py / cr; py %= cr; - printf(" ruling out %d at (%d,%d)\n", + printf("%*s ruling out %d at (%d,%d)\n", + solver_recurse_depth*4, "", pn, 1+px, 1+YUNTRANS(py)); } #endif @@ -959,11 +802,7 @@ static int nsolve_set(struct nsolve_usage *usage, } if (progress) { - sfree(set); - sfree(colidx); - sfree(rowidx); - sfree(grid); - return TRUE; + return +1; } } } @@ -981,26 +820,42 @@ static int nsolve_set(struct nsolve_usage *usage, break; /* done */ } - sfree(set); - sfree(colidx); - sfree(rowidx); - sfree(grid); + return 0; +} - return FALSE; +static struct solver_scratch *solver_new_scratch(struct solver_usage *usage) +{ + struct solver_scratch *scratch = snew(struct solver_scratch); + int cr = usage->cr; + scratch->grid = snewn(cr*cr, unsigned char); + scratch->rowidx = snewn(cr, unsigned char); + scratch->colidx = snewn(cr, unsigned char); + scratch->set = snewn(cr, unsigned char); + return scratch; } -static int nsolve(int c, int r, digit *grid) +static void solver_free_scratch(struct solver_scratch *scratch) { - struct nsolve_usage *usage; + sfree(scratch->set); + sfree(scratch->colidx); + sfree(scratch->rowidx); + sfree(scratch->grid); + sfree(scratch); +} + +static int solver(int c, int r, digit *grid, int maxdiff) +{ + struct solver_usage *usage; + struct solver_scratch *scratch; int cr = c*r; - int x, y, n; + int x, y, n, ret; int diff = DIFF_BLOCK; /* * Set up a usage structure as a clean slate (everything * possible). */ - usage = snew(struct nsolve_usage); + usage = snew(struct solver_usage); usage->c = c; usage->r = r; usage->cr = cr; @@ -1015,13 +870,15 @@ static int nsolve(int c, int r, digit *grid) memset(usage->col, FALSE, cr * cr); memset(usage->blk, FALSE, cr * cr); + scratch = solver_new_scratch(usage); + /* * Place all the clue numbers we are given. */ for (x = 0; x < cr; x++) for (y = 0; y < cr; y++) if (grid[y*cr+x]) - nsolve_place(usage, x, YTRANS(y), grid[y*cr+x]); + solver_place(usage, x, YTRANS(y), grid[y*cr+x]); /* * Now loop over the grid repeatedly trying all permitted modes @@ -1046,45 +903,64 @@ static int nsolve(int c, int r, digit *grid) for (x = 0; x < cr; x += r) for (y = 0; y < r; y++) for (n = 1; n <= cr; n++) - if (!usage->blk[(y*c+(x/r))*cr+n-1] && - nsolve_elim(usage, cubepos(x,y,n), r*cr + if (!usage->blk[(y*c+(x/r))*cr+n-1]) { + ret = solver_elim(usage, cubepos(x,y,n), r*cr #ifdef STANDALONE_SOLVER - , "positional elimination," - " block (%d,%d)", 1+x/r, 1+y + , "positional elimination," + " %d in block (%d,%d)", n, 1+x/r, 1+y #endif - )) { - diff = max(diff, DIFF_BLOCK); - goto cont; + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_BLOCK); + goto cont; + } } + if (maxdiff <= DIFF_BLOCK) + break; + /* * Row-wise positional elimination. */ for (y = 0; y < cr; y++) for (n = 1; n <= cr; n++) - if (!usage->row[y*cr+n-1] && - nsolve_elim(usage, cubepos(0,y,n), cr*cr + if (!usage->row[y*cr+n-1]) { + ret = solver_elim(usage, cubepos(0,y,n), cr*cr #ifdef STANDALONE_SOLVER - , "positional elimination," - " row %d", 1+YUNTRANS(y) + , "positional elimination," + " %d in row %d", n, 1+YUNTRANS(y) #endif - )) { - diff = max(diff, DIFF_SIMPLE); - goto cont; + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SIMPLE); + goto cont; + } } /* * Column-wise positional elimination. */ for (x = 0; x < cr; x++) for (n = 1; n <= cr; n++) - if (!usage->col[x*cr+n-1] && - nsolve_elim(usage, cubepos(x,0,n), cr + if (!usage->col[x*cr+n-1]) { + ret = solver_elim(usage, cubepos(x,0,n), cr #ifdef STANDALONE_SOLVER - , "positional elimination," " column %d", 1+x + , "positional elimination," + " %d in column %d", n, 1+x #endif - )) { - diff = max(diff, DIFF_SIMPLE); - goto cont; + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SIMPLE); + goto cont; + } } /* @@ -1092,39 +968,50 @@ static int nsolve(int c, int r, digit *grid) */ for (x = 0; x < cr; x++) for (y = 0; y < cr; y++) - if (!usage->grid[YUNTRANS(y)*cr+x] && - nsolve_elim(usage, cubepos(x,y,1), 1 + if (!usage->grid[YUNTRANS(y)*cr+x]) { + ret = solver_elim(usage, cubepos(x,y,1), 1 #ifdef STANDALONE_SOLVER - , "numeric elimination at (%d,%d)", 1+x, - 1+YUNTRANS(y) + , "numeric elimination at (%d,%d)", 1+x, + 1+YUNTRANS(y) #endif - )) { - diff = max(diff, DIFF_SIMPLE); - goto cont; + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SIMPLE); + goto cont; + } } + if (maxdiff <= DIFF_SIMPLE) + break; + /* * Intersectional analysis, rows vs blocks. */ for (y = 0; y < cr; y++) for (x = 0; x < cr; x += r) for (n = 1; n <= cr; n++) + /* + * solver_intersect() never returns -1. + */ if (!usage->row[y*cr+n-1] && !usage->blk[((y%r)*c+(x/r))*cr+n-1] && - (nsolve_intersect(usage, cubepos(0,y,n), cr*cr, + (solver_intersect(usage, cubepos(0,y,n), cr*cr, cubepos(x,y%r,n), r*cr #ifdef STANDALONE_SOLVER , "intersectional analysis," - " row %d vs block (%d,%d)", - 1+YUNTRANS(y), 1+x/r, 1+y%r + " %d in row %d vs block (%d,%d)", + n, 1+YUNTRANS(y), 1+x/r, 1+y%r #endif ) || - nsolve_intersect(usage, cubepos(x,y%r,n), r*cr, + solver_intersect(usage, cubepos(x,y%r,n), r*cr, cubepos(0,y,n), cr*cr #ifdef STANDALONE_SOLVER , "intersectional analysis," - " block (%d,%d) vs row %d", - 1+x/r, 1+y%r, 1+YUNTRANS(y) + " %d in block (%d,%d) vs row %d", + n, 1+x/r, 1+y%r, 1+YUNTRANS(y) #endif ))) { diff = max(diff, DIFF_INTERSECT); @@ -1139,65 +1026,83 @@ static int nsolve(int c, int r, digit *grid) for (n = 1; n <= cr; n++) if (!usage->col[x*cr+n-1] && !usage->blk[(y*c+(x/r))*cr+n-1] && - (nsolve_intersect(usage, cubepos(x,0,n), cr, + (solver_intersect(usage, cubepos(x,0,n), cr, cubepos((x/r)*r,y,n), r*cr #ifdef STANDALONE_SOLVER , "intersectional analysis," - " column %d vs block (%d,%d)", - 1+x, 1+x/r, 1+y + " %d in column %d vs block (%d,%d)", + n, 1+x, 1+x/r, 1+y #endif ) || - nsolve_intersect(usage, cubepos((x/r)*r,y,n), r*cr, + solver_intersect(usage, cubepos((x/r)*r,y,n), r*cr, cubepos(x,0,n), cr #ifdef STANDALONE_SOLVER , "intersectional analysis," - " block (%d,%d) vs column %d", - 1+x/r, 1+y, 1+x + " %d in block (%d,%d) vs column %d", + n, 1+x/r, 1+y, 1+x #endif ))) { diff = max(diff, DIFF_INTERSECT); goto cont; } + if (maxdiff <= DIFF_INTERSECT) + break; + /* * Blockwise set elimination. */ for (x = 0; x < cr; x += r) - for (y = 0; y < r; y++) - if (nsolve_set(usage, cubepos(x,y,1), r*cr, 1 + for (y = 0; y < r; y++) { + ret = solver_set(usage, scratch, cubepos(x,y,1), r*cr, 1 #ifdef STANDALONE_SOLVER - , "set elimination, block (%d,%d)", 1+x/r, 1+y + , "set elimination, block (%d,%d)", 1+x/r, 1+y #endif - )) { - diff = max(diff, DIFF_SET); - goto cont; - } + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SET); + goto cont; + } + } /* * Row-wise set elimination. */ - for (y = 0; y < cr; y++) - if (nsolve_set(usage, cubepos(0,y,1), cr*cr, 1 + for (y = 0; y < cr; y++) { + ret = solver_set(usage, scratch, cubepos(0,y,1), cr*cr, 1 #ifdef STANDALONE_SOLVER - , "set elimination, row %d", 1+YUNTRANS(y) + , "set elimination, row %d", 1+YUNTRANS(y) #endif - )) { - diff = max(diff, DIFF_SET); - goto cont; - } + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SET); + goto cont; + } + } /* * Column-wise set elimination. */ - for (x = 0; x < cr; x++) - if (nsolve_set(usage, cubepos(x,0,1), cr, 1 + for (x = 0; x < cr; x++) { + ret = solver_set(usage, scratch, cubepos(x,0,1), cr, 1 #ifdef STANDALONE_SOLVER - , "set elimination, column %d", 1+x + , "set elimination, column %d", 1+x #endif - )) { - diff = max(diff, DIFF_SET); - goto cont; - } + ); + if (ret < 0) { + diff = DIFF_IMPOSSIBLE; + goto got_result; + } else if (ret > 0) { + diff = max(diff, DIFF_SET); + goto cont; + } + } /* * If we reach here, we have made no deductions in this @@ -1206,21 +1111,396 @@ static int nsolve(int c, int r, digit *grid) break; } + /* + * Last chance: if we haven't fully solved the puzzle yet, try + * recursing based on guesses for a particular square. We pick + * one of the most constrained empty squares we can find, which + * has the effect of pruning the search tree as much as + * possible. + */ + if (maxdiff >= DIFF_RECURSIVE) { + int best, bestcount; + + best = -1; + bestcount = cr+1; + + for (y = 0; y < cr; y++) + for (x = 0; x < cr; x++) + if (!grid[y*cr+x]) { + int count; + + /* + * An unfilled square. Count the number of + * possible digits in it. + */ + count = 0; + for (n = 1; n <= cr; n++) + if (cube(x,YTRANS(y),n)) + count++; + + /* + * We should have found any impossibilities + * already, so this can safely be an assert. + */ + assert(count > 1); + + if (count < bestcount) { + bestcount = count; + best = y*cr+x; + } + } + + if (best != -1) { + int i, j; + digit *list, *ingrid, *outgrid; + + diff = DIFF_IMPOSSIBLE; /* no solution found yet */ + + /* + * Attempt recursion. + */ + y = best / cr; + x = best % cr; + + list = snewn(cr, digit); + ingrid = snewn(cr * cr, digit); + outgrid = snewn(cr * cr, digit); + memcpy(ingrid, grid, cr * cr); + + /* Make a list of the possible digits. */ + for (j = 0, n = 1; n <= cr; n++) + if (cube(x,YTRANS(y),n)) + list[j++] = n; + +#ifdef STANDALONE_SOLVER + if (solver_show_working) { + char *sep = ""; + printf("%*srecursing on (%d,%d) [", + solver_recurse_depth*4, "", x, y); + for (i = 0; i < j; i++) { + printf("%s%d", sep, list[i]); + sep = " or "; + } + printf("]\n"); + } +#endif + + /* + * And step along the list, recursing back into the + * main solver at every stage. + */ + for (i = 0; i < j; i++) { + int ret; + + memcpy(outgrid, ingrid, cr * cr); + outgrid[y*cr+x] = list[i]; + +#ifdef STANDALONE_SOLVER + if (solver_show_working) + printf("%*sguessing %d at (%d,%d)\n", + solver_recurse_depth*4, "", list[i], x, y); + solver_recurse_depth++; +#endif + + ret = solver(c, r, outgrid, maxdiff); + +#ifdef STANDALONE_SOLVER + solver_recurse_depth--; + if (solver_show_working) { + printf("%*sretracting %d at (%d,%d)\n", + solver_recurse_depth*4, "", list[i], x, y); + } +#endif + + /* + * If we have our first solution, copy it into the + * grid we will return. + */ + if (diff == DIFF_IMPOSSIBLE && ret != DIFF_IMPOSSIBLE) + memcpy(grid, outgrid, cr*cr); + + if (ret == DIFF_AMBIGUOUS) + diff = DIFF_AMBIGUOUS; + else if (ret == DIFF_IMPOSSIBLE) + /* do not change our return value */; + else { + /* the recursion turned up exactly one solution */ + if (diff == DIFF_IMPOSSIBLE) + diff = DIFF_RECURSIVE; + else + diff = DIFF_AMBIGUOUS; + } + + /* + * As soon as we've found more than one solution, + * give up immediately. + */ + if (diff == DIFF_AMBIGUOUS) + break; + } + + sfree(outgrid); + sfree(ingrid); + sfree(list); + } + + } else { + /* + * We're forbidden to use recursion, so we just see whether + * our grid is fully solved, and return DIFF_IMPOSSIBLE + * otherwise. + */ + for (y = 0; y < cr; y++) + for (x = 0; x < cr; x++) + if (!grid[y*cr+x]) + diff = DIFF_IMPOSSIBLE; + } + + got_result:; + +#ifdef STANDALONE_SOLVER + if (solver_show_working) + printf("%*s%s found\n", + solver_recurse_depth*4, "", + diff == DIFF_IMPOSSIBLE ? "no solution" : + diff == DIFF_AMBIGUOUS ? "multiple solutions" : + "one solution"); +#endif + sfree(usage->cube); sfree(usage->row); sfree(usage->col); sfree(usage->blk); sfree(usage); - for (x = 0; x < cr; x++) - for (y = 0; y < cr; y++) - if (!grid[y*cr+x]) - return DIFF_IMPOSSIBLE; + solver_free_scratch(scratch); + return diff; } /* ---------------------------------------------------------------------- - * End of non-recursive solver code. + * End of solver code. + */ + +/* ---------------------------------------------------------------------- + * Solo filled-grid generator. + * + * This grid generator works by essentially trying to solve a grid + * starting from no clues, and not worrying that there's more than + * one possible solution. Unfortunately, it isn't computationally + * feasible to do this by calling the above solver with an empty + * grid, because that one needs to allocate a lot of scratch space + * at every recursion level. Instead, I have a much simpler + * algorithm which I shamelessly copied from a Python solver + * written by Andrew Wilkinson (which is GPLed, but I've reused + * only ideas and no code). It mostly just does the obvious + * recursive thing: pick an empty square, put one of the possible + * digits in it, recurse until all squares are filled, backtrack + * and change some choices if necessary. + * + * The clever bit is that every time it chooses which square to + * fill in next, it does so by counting the number of _possible_ + * numbers that can go in each square, and it prioritises so that + * it picks a square with the _lowest_ number of possibilities. The + * idea is that filling in lots of the obvious bits (particularly + * any squares with only one possibility) will cut down on the list + * of possibilities for other squares and hence reduce the enormous + * search space as much as possible as early as possible. + */ + +/* + * Internal data structure used in gridgen to keep track of + * progress. + */ +struct gridgen_coord { int x, y, r; }; +struct gridgen_usage { + int c, r, cr; /* cr == c*r */ + /* grid is a copy of the input grid, modified as we go along */ + digit *grid; + /* row[y*cr+n-1] TRUE if digit n has been placed in row y */ + unsigned char *row; + /* col[x*cr+n-1] TRUE if digit n has been placed in row x */ + unsigned char *col; + /* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */ + unsigned char *blk; + /* This lists all the empty spaces remaining in the grid. */ + struct gridgen_coord *spaces; + int nspaces; + /* If we need randomisation in the solve, this is our random state. */ + random_state *rs; +}; + +/* + * The real recursive step in the generating function. + */ +static int gridgen_real(struct gridgen_usage *usage, digit *grid) +{ + int c = usage->c, r = usage->r, cr = usage->cr; + int i, j, n, sx, sy, bestm, bestr, ret; + int *digits; + + /* + * Firstly, check for completion! If there are no spaces left + * in the grid, we have a solution. + */ + if (usage->nspaces == 0) { + memcpy(grid, usage->grid, cr * cr); + return TRUE; + } + + /* + * Otherwise, there must be at least one space. Find the most + * constrained space, using the `r' field as a tie-breaker. + */ + bestm = cr+1; /* so that any space will beat it */ + bestr = 0; + i = sx = sy = -1; + for (j = 0; j < usage->nspaces; j++) { + int x = usage->spaces[j].x, y = usage->spaces[j].y; + int m; + + /* + * Find the number of digits that could go in this space. + */ + m = 0; + for (n = 0; n < cr; n++) + if (!usage->row[y*cr+n] && !usage->col[x*cr+n] && + !usage->blk[((y/c)*c+(x/r))*cr+n]) + m++; + + if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) { + bestm = m; + bestr = usage->spaces[j].r; + sx = x; + sy = y; + i = j; + } + } + + /* + * Swap that square into the final place in the spaces array, + * so that decrementing nspaces will remove it from the list. + */ + if (i != usage->nspaces-1) { + struct gridgen_coord t; + t = usage->spaces[usage->nspaces-1]; + usage->spaces[usage->nspaces-1] = usage->spaces[i]; + usage->spaces[i] = t; + } + + /* + * Now we've decided which square to start our recursion at, + * simply go through all possible values, shuffling them + * randomly first if necessary. + */ + digits = snewn(bestm, int); + j = 0; + for (n = 0; n < cr; n++) + if (!usage->row[sy*cr+n] && !usage->col[sx*cr+n] && + !usage->blk[((sy/c)*c+(sx/r))*cr+n]) { + digits[j++] = n+1; + } + + if (usage->rs) + shuffle(digits, j, sizeof(*digits), usage->rs); + + /* And finally, go through the digit list and actually recurse. */ + ret = FALSE; + for (i = 0; i < j; i++) { + n = digits[i]; + + /* Update the usage structure to reflect the placing of this digit. */ + usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = + usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = TRUE; + usage->grid[sy*cr+sx] = n; + usage->nspaces--; + + /* Call the solver recursively. Stop when we find a solution. */ + if (gridgen_real(usage, grid)) + ret = TRUE; + + /* Revert the usage structure. */ + usage->row[sy*cr+n-1] = usage->col[sx*cr+n-1] = + usage->blk[((sy/c)*c+(sx/r))*cr+n-1] = FALSE; + usage->grid[sy*cr+sx] = 0; + usage->nspaces++; + + if (ret) + break; + } + + sfree(digits); + return ret; +} + +/* + * Entry point to generator. You give it dimensions and a starting + * grid, which is simply an array of cr*cr digits. + */ +static void gridgen(int c, int r, digit *grid, random_state *rs) +{ + struct gridgen_usage *usage; + int x, y, cr = c*r; + + /* + * Clear the grid to start with. + */ + memset(grid, 0, cr*cr); + + /* + * Create a gridgen_usage structure. + */ + usage = snew(struct gridgen_usage); + + usage->c = c; + usage->r = r; + usage->cr = cr; + + usage->grid = snewn(cr * cr, digit); + memcpy(usage->grid, grid, cr * cr); + + usage->row = snewn(cr * cr, unsigned char); + usage->col = snewn(cr * cr, unsigned char); + usage->blk = snewn(cr * cr, unsigned char); + memset(usage->row, FALSE, cr * cr); + memset(usage->col, FALSE, cr * cr); + memset(usage->blk, FALSE, cr * cr); + + usage->spaces = snewn(cr * cr, struct gridgen_coord); + usage->nspaces = 0; + + usage->rs = rs; + + /* + * Initialise the list of grid spaces. + */ + for (y = 0; y < cr; y++) { + for (x = 0; x < cr; x++) { + usage->spaces[usage->nspaces].x = x; + usage->spaces[usage->nspaces].y = y; + usage->spaces[usage->nspaces].r = random_bits(rs, 31); + usage->nspaces++; + } + } + + /* + * Run the real generator function. + */ + gridgen_real(usage, grid); + + /* + * Clean up the usage structure now we have our answer. + */ + sfree(usage->spaces); + sfree(usage->blk); + sfree(usage->col); + sfree(usage->row); + sfree(usage->grid); + sfree(usage); +} + +/* ---------------------------------------------------------------------- + * End of grid generator code. */ /* @@ -1287,82 +1567,113 @@ static int check_valid(int c, int r, digit *grid) return TRUE; } -static void symmetry_limit(game_params *params, int *xlim, int *ylim, int s) +static int symmetries(game_params *params, int x, int y, int *output, int s) { int c = params->c, r = params->r, cr = c*r; + int i = 0; + +#define ADD(x,y) (*output++ = (x), *output++ = (y), i++) + + ADD(x, y); switch (s) { case SYMM_NONE: - *xlim = *ylim = cr; - break; + break; /* just x,y is all we need */ case SYMM_ROT2: - *xlim = (cr+1) / 2; - *ylim = cr; - break; - case SYMM_REF4: + ADD(cr - 1 - x, cr - 1 - y); + break; case SYMM_ROT4: - *xlim = *ylim = (cr+1) / 2; - break; + ADD(cr - 1 - y, x); + ADD(y, cr - 1 - x); + ADD(cr - 1 - x, cr - 1 - y); + break; + case SYMM_REF2: + ADD(cr - 1 - x, y); + break; + case SYMM_REF2D: + ADD(y, x); + break; + case SYMM_REF4: + ADD(cr - 1 - x, y); + ADD(x, cr - 1 - y); + ADD(cr - 1 - x, cr - 1 - y); + break; + case SYMM_REF4D: + ADD(y, x); + ADD(cr - 1 - x, cr - 1 - y); + ADD(cr - 1 - y, cr - 1 - x); + break; + case SYMM_REF8: + ADD(cr - 1 - x, y); + ADD(x, cr - 1 - y); + ADD(cr - 1 - x, cr - 1 - y); + ADD(y, x); + ADD(y, cr - 1 - x); + ADD(cr - 1 - y, x); + ADD(cr - 1 - y, cr - 1 - x); + break; } + +#undef ADD + + return i; } -static int symmetries(game_params *params, int x, int y, int *output, int s) +static char *encode_solve_move(int cr, digit *grid) { - int c = params->c, r = params->r, cr = c*r; - int i = 0; + int i, len; + char *ret, *p, *sep; - *output++ = x; - *output++ = y; - i++; + /* + * It's surprisingly easy to work out _exactly_ how long this + * string needs to be. To decimal-encode all the numbers from 1 + * to n: + * + * - every number has a units digit; total is n. + * - all numbers above 9 have a tens digit; total is max(n-9,0). + * - all numbers above 99 have a hundreds digit; total is max(n-99,0). + * - and so on. + */ + len = 0; + for (i = 1; i <= cr; i *= 10) + len += max(cr - i + 1, 0); + len += cr; /* don't forget the commas */ + len *= cr; /* there are cr rows of these */ - switch (s) { - case SYMM_NONE: - break; /* just x,y is all we need */ - case SYMM_REF4: - case SYMM_ROT4: - switch (s) { - case SYMM_REF4: - *output++ = cr - 1 - x; - *output++ = y; - i++; - - *output++ = x; - *output++ = cr - 1 - y; - i++; - break; - case SYMM_ROT4: - *output++ = cr - 1 - y; - *output++ = x; - i++; - - *output++ = y; - *output++ = cr - 1 - x; - i++; - break; - } - /* fall through */ - case SYMM_ROT2: - *output++ = cr - 1 - x; - *output++ = cr - 1 - y; - i++; - break; + /* + * Now len is one bigger than the total size of the + * comma-separated numbers (because we counted an + * additional leading comma). We need to have a leading S + * and a trailing NUL, so we're off by one in total. + */ + len++; + + ret = snewn(len, char); + p = ret; + *p++ = 'S'; + sep = ""; + for (i = 0; i < cr*cr; i++) { + p += sprintf(p, "%s%d", sep, grid[i]); + sep = ","; } + *p++ = '\0'; + assert(p - ret == len); - return i; + return ret; } -static char *new_game_seed(game_params *params, random_state *rs) +static char *new_game_desc(game_params *params, random_state *rs, + char **aux, int interactive) { int c = params->c, r = params->r, cr = c*r; int area = cr*cr; digit *grid, *grid2; struct xy { int x, y; } *locs; int nlocs; - int ret; - char *seed; + char *desc; int coords[16], ncoords; - int xlim, ylim; - int maxdiff; + int *symmclasses, nsymmclasses; + int maxdiff, recursing; /* * Adjust the maximum difficulty level to be consistent with @@ -1379,25 +1690,63 @@ static char *new_game_seed(game_params *params, random_state *rs) grid2 = snewn(area, digit); /* + * Find the set of equivalence classes of squares permitted + * by the selected symmetry. We do this by enumerating all + * the grid squares which have no symmetric companion + * sorting lower than themselves. + */ + nsymmclasses = 0; + symmclasses = snewn(cr * cr, int); + { + int x, y; + + for (y = 0; y < cr; y++) + for (x = 0; x < cr; x++) { + int i = y*cr+x; + int j; + + ncoords = symmetries(params, x, y, coords, params->symm); + for (j = 0; j < ncoords; j++) + if (coords[2*j+1]*cr+coords[2*j] < i) + break; + if (j == ncoords) + symmclasses[nsymmclasses++] = i; + } + } + + /* * Loop until we get a grid of the required difficulty. This is * nasty, but it seems to be unpleasantly hard to generate * difficult grids otherwise. */ do { /* - * Start the recursive solver with an empty grid to generate a - * random solved state. + * Generate a random solved state. */ - memset(grid, 0, area); - ret = rsolve(c, r, grid, rs, 1); - assert(ret == 1); + gridgen(c, r, grid, rs); assert(check_valid(c, r, grid)); + /* + * Save the solved grid in aux. + */ + { + /* + * We might already have written *aux the last time we + * went round this loop, in which case we should free + * the old aux before overwriting it with the new one. + */ + if (*aux) { + sfree(*aux); + } + + *aux = encode_solve_move(cr, grid); + } + /* * Now we have a solved grid, start removing things from it * while preserving solubility. */ - symmetry_limit(params, &xlim, &ylim, params->symm); + recursing = FALSE; while (1) { int x, y, i, j; @@ -1407,33 +1756,30 @@ static char *new_game_seed(game_params *params, random_state *rs) */ nlocs = 0; - for (x = 0; x < xlim; x++) - for (y = 0; y < ylim; y++) - if (grid[y*cr+x]) { - locs[nlocs].x = x; - locs[nlocs].y = y; - nlocs++; - } + for (i = 0; i < nsymmclasses; i++) { + x = symmclasses[i] % cr; + y = symmclasses[i] / cr; + if (grid[y*cr+x]) { + locs[nlocs].x = x; + locs[nlocs].y = y; + nlocs++; + } + } /* * Now shuffle that list. */ - for (i = nlocs; i > 1; i--) { - int p = random_upto(rs, i); - if (p != i-1) { - struct xy t = locs[p]; - locs[p] = locs[i-1]; - locs[i-1] = t; - } - } + shuffle(locs, nlocs, sizeof(*locs), rs); /* * Now loop over the shuffled list and, for each element, * see whether removing that element (and its reflections) * from the grid will still leave the grid soluble by - * nsolve. + * solver. */ for (i = 0; i < nlocs; i++) { + int ret; + x = locs[i].x; y = locs[i].y; @@ -1442,7 +1788,8 @@ static char *new_game_seed(game_params *params, random_state *rs) for (j = 0; j < ncoords; j++) grid2[coords[2*j+1]*cr+coords[2*j]] = 0; - if (nsolve(c, r, grid2) <= maxdiff) { + ret = solver(c, r, grid2, maxdiff); + if (ret != DIFF_IMPOSSIBLE && ret != DIFF_AMBIGUOUS) { for (j = 0; j < ncoords; j++) grid[coords[2*j+1]*cr+coords[2*j]] = 0; break; @@ -1451,29 +1798,31 @@ static char *new_game_seed(game_params *params, random_state *rs) if (i == nlocs) { /* - * There was nothing we could remove without destroying - * solvability. + * There was nothing we could remove without + * destroying solvability. Give up. */ break; } } memcpy(grid2, grid, area); - } while (nsolve(c, r, grid2) != maxdiff); + } while (solver(c, r, grid2, maxdiff) < maxdiff); sfree(grid2); sfree(locs); + sfree(symmclasses); + /* * Now we have the grid as it will be presented to the user. - * Encode it in a game seed. + * Encode it in a game desc. */ { char *p; int run, i; - seed = snewn(5 * area, char); - p = seed; + desc = snewn(5 * area, char); + p = desc; run = 0; for (i = 0; i <= area; i++) { int n = (i < area ? grid[i] : -1); @@ -1495,7 +1844,7 @@ static char *new_game_seed(game_params *params, random_state *rs) * bottom right, there's no point putting an * unnecessary _ before or after it. */ - if (p > seed && n > 0) + if (p > desc && n > 0) *p++ = '_'; } if (n > 0) @@ -1503,33 +1852,33 @@ static char *new_game_seed(game_params *params, random_state *rs) run = 0; } } - assert(p - seed < 5 * area); + assert(p - desc < 5 * area); *p++ = '\0'; - seed = sresize(seed, p - seed, char); + desc = sresize(desc, p - desc, char); } sfree(grid); - return seed; + return desc; } -static char *validate_seed(game_params *params, char *seed) +static char *validate_desc(game_params *params, char *desc) { int area = params->r * params->r * params->c * params->c; int squares = 0; - while (*seed) { - int n = *seed++; + while (*desc) { + int n = *desc++; if (n >= 'a' && n <= 'z') { squares += n - 'a' + 1; } else if (n == '_') { /* do nothing */; } else if (n > '0' && n <= '9') { squares++; - while (*seed >= '0' && *seed <= '9') - seed++; + while (*desc >= '0' && *desc <= '9') + desc++; } else - return "Invalid character in game specification"; + return "Invalid character in game description"; } if (squares < area) @@ -1541,7 +1890,7 @@ static char *validate_seed(game_params *params, char *seed) return NULL; } -static game_state *new_game(game_params *params, char *seed) +static game_state *new_game(midend_data *me, game_params *params, char *desc) { game_state *state = snew(game_state); int c = params->c, r = params->r, cr = c*r, area = cr * cr; @@ -1551,14 +1900,16 @@ static game_state *new_game(game_params *params, char *seed) state->r = params->r; state->grid = snewn(area, digit); + state->pencil = snewn(area * cr, unsigned char); + memset(state->pencil, 0, area * cr); state->immutable = snewn(area, unsigned char); memset(state->immutable, FALSE, area); - state->completed = FALSE; + state->completed = state->cheated = FALSE; i = 0; - while (*seed) { - int n = *seed++; + while (*desc) { + int n = *desc++; if (n >= 'a' && n <= 'z') { int run = n - 'a' + 1; assert(i + run <= area); @@ -1569,9 +1920,9 @@ static game_state *new_game(game_params *params, char *seed) } else if (n > '0' && n <= '9') { assert(i < area); state->immutable[i] = TRUE; - state->grid[i++] = atoi(seed-1); - while (*seed >= '0' && *seed <= '9') - seed++; + state->grid[i++] = atoi(desc-1); + while (*desc >= '0' && *desc <= '9') + desc++; } else { assert(!"We can't get here"); } @@ -1592,10 +1943,14 @@ static game_state *dup_game(game_state *state) ret->grid = snewn(area, digit); memcpy(ret->grid, state->grid, area); + ret->pencil = snewn(area * cr, unsigned char); + memcpy(ret->pencil, state->pencil, area * cr); + ret->immutable = snewn(area, unsigned char); memcpy(ret->immutable, state->immutable, area); ret->completed = state->completed; + ret->cheated = state->cheated; return ret; } @@ -1603,10 +1958,111 @@ static game_state *dup_game(game_state *state) static void free_game(game_state *state) { sfree(state->immutable); + sfree(state->pencil); sfree(state->grid); sfree(state); } +static char *solve_game(game_state *state, game_state *currstate, + char *ai, char **error) +{ + int c = state->c, r = state->r, cr = c*r; + char *ret; + digit *grid; + int solve_ret; + + /* + * If we already have the solution in ai, save ourselves some + * time. + */ + if (ai) + return dupstr(ai); + + grid = snewn(cr*cr, digit); + memcpy(grid, state->grid, cr*cr); + solve_ret = solver(c, r, grid, DIFF_RECURSIVE); + + *error = NULL; + + if (solve_ret == DIFF_IMPOSSIBLE) + *error = "No solution exists for this puzzle"; + else if (solve_ret == DIFF_AMBIGUOUS) + *error = "Multiple solutions exist for this puzzle"; + + if (*error) { + sfree(grid); + return NULL; + } + + ret = encode_solve_move(cr, grid); + + sfree(grid); + + return ret; +} + +static char *grid_text_format(int c, int r, digit *grid) +{ + int cr = c*r; + int x, y; + int maxlen; + char *ret, *p; + + /* + * There are cr lines of digits, plus r-1 lines of block + * separators. Each line contains cr digits, cr-1 separating + * spaces, and c-1 two-character block separators. Thus, the + * total length of a line is 2*cr+2*c-3 (not counting the + * newline), and there are cr+r-1 of them. + */ + maxlen = (cr+r-1) * (2*cr+2*c-2); + ret = snewn(maxlen+1, char); + p = ret; + + for (y = 0; y < cr; y++) { + for (x = 0; x < cr; x++) { + int ch = grid[y * cr + x]; + if (ch == 0) + ch = ' '; + else if (ch <= 9) + ch = '0' + ch; + else + ch = 'a' + ch-10; + *p++ = ch; + if (x+1 < cr) { + *p++ = ' '; + if ((x+1) % r == 0) { + *p++ = '|'; + *p++ = ' '; + } + } + } + *p++ = '\n'; + if (y+1 < cr && (y+1) % c == 0) { + for (x = 0; x < cr; x++) { + *p++ = '-'; + if (x+1 < cr) { + *p++ = '-'; + if ((x+1) % r == 0) { + *p++ = '+'; + *p++ = '-'; + } + } + } + *p++ = '\n'; + } + } + + assert(p - ret == maxlen); + *p = '\0'; + return ret; +} + +static char *game_text_format(game_state *state) +{ + return grid_text_format(state->c, state->r, state->grid); +} + struct game_ui { /* * These are the coordinates of the currently highlighted @@ -1615,6 +2071,11 @@ struct game_ui { * enter that number or letter in the grid. */ int hx, hy; + /* + * This indicates whether the current highlight is a + * pencil-mark one or a real one. + */ + int hpencil; }; static game_ui *new_ui(game_state *state) @@ -1622,6 +2083,7 @@ static game_ui *new_ui(game_state *state) game_ui *ui = snew(game_ui); ui->hx = ui->hy = -1; + ui->hpencil = 0; return ui; } @@ -1631,24 +2093,84 @@ static void free_ui(game_ui *ui) sfree(ui); } -static game_state *make_move(game_state *from, game_ui *ui, int x, int y, - int button) +static char *encode_ui(game_ui *ui) { - int c = from->c, r = from->r, cr = c*r; + return NULL; +} + +static void decode_ui(game_ui *ui, char *encoding) +{ +} + +static void game_changed_state(game_ui *ui, game_state *oldstate, + game_state *newstate) +{ + int c = newstate->c, r = newstate->r, cr = c*r; + /* + * We prevent pencil-mode highlighting of a filled square. So + * if the user has just filled in a square which we had a + * pencil-mode highlight in (by Undo, or by Redo, or by Solve), + * then we cancel the highlight. + */ + if (ui->hx >= 0 && ui->hy >= 0 && ui->hpencil && + newstate->grid[ui->hy * cr + ui->hx] != 0) { + ui->hx = ui->hy = -1; + } +} + +struct game_drawstate { + int started; + int c, r, cr; + int tilesize; + digit *grid; + unsigned char *pencil; + unsigned char *hl; + /* This is scratch space used within a single call to game_redraw. */ + int *entered_items; +}; + +static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, + int x, int y, int button) +{ + int c = state->c, r = state->r, cr = c*r; int tx, ty; - game_state *ret; + char buf[80]; + + button &= ~MOD_MASK; tx = (x + TILE_SIZE - BORDER) / TILE_SIZE - 1; ty = (y + TILE_SIZE - BORDER) / TILE_SIZE - 1; - if (tx >= 0 && tx < cr && ty >= 0 && ty < cr && button == LEFT_BUTTON) { - if (tx == ui->hx && ty == ui->hy) { - ui->hx = ui->hy = -1; - } else { - ui->hx = tx; - ui->hy = ty; - } - return from; /* UI activity occurred */ + if (tx >= 0 && tx < cr && ty >= 0 && ty < cr) { + if (button == LEFT_BUTTON) { + if (state->immutable[ty*cr+tx]) { + ui->hx = ui->hy = -1; + } else if (tx == ui->hx && ty == ui->hy && ui->hpencil == 0) { + ui->hx = ui->hy = -1; + } else { + ui->hx = tx; + ui->hy = ty; + ui->hpencil = 0; + } + return ""; /* UI activity occurred */ + } + if (button == RIGHT_BUTTON) { + /* + * Pencil-mode highlighting for non filled squares. + */ + if (state->grid[ty*cr+tx] == 0) { + if (tx == ui->hx && ty == ui->hy && ui->hpencil) { + ui->hx = ui->hy = -1; + } else { + ui->hpencil = 1; + ui->hx = tx; + ui->hy = ty; + } + } else { + ui->hx = ui->hy = -1; + } + return ""; /* UI activity occurred */ + } } if (ui->hx != -1 && ui->hy != -1 && @@ -1664,47 +2186,108 @@ static game_state *make_move(game_state *from, game_ui *ui, int x, int y, if (button == ' ') n = 0; - if (from->immutable[ui->hy*cr+ui->hx]) - return NULL; /* can't overwrite this square */ + /* + * Can't overwrite this square. In principle this shouldn't + * happen anyway because we should never have even been + * able to highlight the square, but it never hurts to be + * careful. + */ + if (state->immutable[ui->hy*cr+ui->hx]) + return NULL; - ret = dup_game(from); - ret->grid[ui->hy*cr+ui->hx] = n; - ui->hx = ui->hy = -1; + /* + * Can't make pencil marks in a filled square. In principle + * this shouldn't happen anyway because we should never + * have even been able to pencil-highlight the square, but + * it never hurts to be careful. + */ + if (ui->hpencil && state->grid[ui->hy*cr+ui->hx]) + return NULL; - /* - * We've made a real change to the grid. Check to see - * if the game has been completed. - */ - if (!ret->completed && check_valid(c, r, ret->grid)) { - ret->completed = TRUE; - } + sprintf(buf, "%c%d,%d,%d", + (char)(ui->hpencil && n > 0 ? 'P' : 'R'), ui->hx, ui->hy, n); - return ret; /* made a valid move */ + ui->hx = ui->hy = -1; + + return dupstr(buf); } return NULL; } +static game_state *execute_move(game_state *from, char *move) +{ + int c = from->c, r = from->r, cr = c*r; + game_state *ret; + int x, y, n; + + if (move[0] == 'S') { + char *p; + + ret = dup_game(from); + ret->completed = ret->cheated = TRUE; + + p = move+1; + for (n = 0; n < cr*cr; n++) { + ret->grid[n] = atoi(p); + + if (!*p || ret->grid[n] < 1 || ret->grid[n] > cr) { + free_game(ret); + return NULL; + } + + while (*p && isdigit((unsigned char)*p)) p++; + if (*p == ',') p++; + } + + return ret; + } else if ((move[0] == 'P' || move[0] == 'R') && + sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 && + x >= 0 && x < cr && y >= 0 && y < cr && n >= 0 && n <= cr) { + + ret = dup_game(from); + if (move[0] == 'P' && n > 0) { + int index = (y*cr+x) * cr + (n-1); + ret->pencil[index] = !ret->pencil[index]; + } else { + ret->grid[y*cr+x] = n; + memset(ret->pencil + (y*cr+x)*cr, 0, cr); + + /* + * We've made a real change to the grid. Check to see + * if the game has been completed. + */ + if (!ret->completed && check_valid(c, r, ret->grid)) { + ret->completed = TRUE; + } + } + return ret; + } else + return NULL; /* couldn't parse move string */ +} + /* ---------------------------------------------------------------------- * Drawing routines. */ -struct game_drawstate { - int started; - int c, r, cr; - digit *grid; - unsigned char *hl; -}; - -#define XSIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) -#define YSIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) +#define SIZE(cr) ((cr) * TILE_SIZE + 2*BORDER + 1) +#define GETTILESIZE(cr, w) ( (double)(w-1) / (double)(cr+1) ) -static void game_size(game_params *params, int *x, int *y) +static void game_compute_size(game_params *params, int tilesize, + int *x, int *y) { - int c = params->c, r = params->r, cr = c*r; + /* Ick: fake up `ds->tilesize' for macro expansion purposes */ + struct { int tilesize; } ads, *ds = &ads; + ads.tilesize = tilesize; - *x = XSIZE(cr); - *y = YSIZE(cr); + *x = SIZE(params->c * params->r); + *y = SIZE(params->c * params->r); +} + +static void game_set_size(game_drawstate *ds, game_params *params, + int tilesize) +{ + ds->tilesize = tilesize; } static float *game_colours(frontend *fe, game_state *state, int *ncolours) @@ -1729,6 +2312,14 @@ static float *game_colours(frontend *fe, game_state *state, int *ncolours) ret[COL_HIGHLIGHT * 3 + 1] = 0.85F * ret[COL_BACKGROUND * 3 + 1]; ret[COL_HIGHLIGHT * 3 + 2] = 0.85F * ret[COL_BACKGROUND * 3 + 2]; + ret[COL_ERROR * 3 + 0] = 1.0F; + ret[COL_ERROR * 3 + 1] = 0.0F; + ret[COL_ERROR * 3 + 2] = 0.0F; + + ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; + ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; + ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2]; + *ncolours = NCOLOURS; return ret; } @@ -1744,16 +2335,21 @@ static game_drawstate *game_new_drawstate(game_state *state) ds->cr = cr; ds->grid = snewn(cr*cr, digit); memset(ds->grid, 0, cr*cr); + ds->pencil = snewn(cr*cr*cr, digit); + memset(ds->pencil, 0, cr*cr*cr); ds->hl = snewn(cr*cr, unsigned char); memset(ds->hl, 0, cr*cr); - + ds->entered_items = snewn(cr*cr, int); + ds->tilesize = 0; /* not decided yet */ return ds; } static void game_free_drawstate(game_drawstate *ds) { sfree(ds->hl); + sfree(ds->pencil); sfree(ds->grid); + sfree(ds->entered_items); sfree(ds); } @@ -1765,7 +2361,9 @@ static void draw_number(frontend *fe, game_drawstate *ds, game_state *state, int cx, cy, cw, ch; char str[2]; - if (ds->grid[y*cr+x] == state->grid[y*cr+x] && ds->hl[y*cr+x] == hl) + if (ds->grid[y*cr+x] == state->grid[y*cr+x] && + ds->hl[y*cr+x] == hl && + !memcmp(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr)) return; /* no change required */ tx = BORDER + x * TILE_SIZE + 2; @@ -1787,9 +2385,20 @@ static void draw_number(frontend *fe, game_drawstate *ds, game_state *state, clip(fe, cx, cy, cw, ch); - /* background needs erasing? */ - if (ds->grid[y*cr+x] || ds->hl[y*cr+x] != hl) - draw_rect(fe, cx, cy, cw, ch, hl ? COL_HIGHLIGHT : COL_BACKGROUND); + /* background needs erasing */ + draw_rect(fe, cx, cy, cw, ch, (hl & 15) == 1 ? COL_HIGHLIGHT : COL_BACKGROUND); + + /* pencil-mode highlight */ + if ((hl & 15) == 2) { + int coords[6]; + coords[0] = cx; + coords[1] = cy; + coords[2] = cx+cw/2; + coords[3] = cy; + coords[4] = cx; + coords[5] = cy+ch/2; + draw_polygon(fe, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT); + } /* new number needs drawing? */ if (state->grid[y*cr+x]) { @@ -1799,7 +2408,45 @@ static void draw_number(frontend *fe, game_drawstate *ds, game_state *state, str[0] += 'a' - ('9'+1); draw_text(fe, tx + TILE_SIZE/2, ty + TILE_SIZE/2, FONT_VARIABLE, TILE_SIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE, - state->immutable[y*cr+x] ? COL_CLUE : COL_USER, str); + state->immutable[y*cr+x] ? COL_CLUE : (hl & 16) ? COL_ERROR : COL_USER, str); + } else { + int i, j, npencil; + int pw, ph, pmax, fontsize; + + /* count the pencil marks required */ + for (i = npencil = 0; i < cr; i++) + if (state->pencil[(y*cr+x)*cr+i]) + npencil++; + + /* + * It's not sensible to arrange pencil marks in the same + * layout as the squares within a block, because this leads + * to the font being too small. Instead, we arrange pencil + * marks in the nearest thing we can to a square layout, + * and we adjust the square layout depending on the number + * of pencil marks in the square. + */ + for (pw = 1; pw * pw < npencil; pw++); + if (pw < 3) pw = 3; /* otherwise it just looks _silly_ */ + ph = (npencil + pw - 1) / pw; + if (ph < 2) ph = 2; /* likewise */ + pmax = max(pw, ph); + fontsize = TILE_SIZE/(pmax*(11-pmax)/8); + + for (i = j = 0; i < cr; i++) + if (state->pencil[(y*cr+x)*cr+i]) { + int dx = j % pw, dy = j / pw; + + str[1] = '\0'; + str[0] = i + '1'; + if (str[0] > '9') + str[0] += 'a' - ('9'+1); + draw_text(fe, tx + (4*dx+3) * TILE_SIZE / (4*pw+2), + ty + (4*dy+3) * TILE_SIZE / (4*ph+2), + FONT_VARIABLE, fontsize, + ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str); + j++; + } } unclip(fe); @@ -1807,6 +2454,7 @@ static void draw_number(frontend *fe, game_drawstate *ds, game_state *state, draw_update(fe, cx, cy, cw, ch); ds->grid[y*cr+x] = state->grid[y*cr+x]; + memcpy(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr); ds->hl[y*cr+x] = hl; } @@ -1824,7 +2472,7 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, * all games should start by drawing a big * background-colour rectangle covering the whole window. */ - draw_rect(fe, 0, 0, XSIZE(cr), YSIZE(cr), COL_BACKGROUND); + draw_rect(fe, 0, 0, SIZE(cr), SIZE(cr), COL_BACKGROUND); /* * Draw the grid. @@ -1842,15 +2490,47 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, } /* + * This array is used to keep track of rows, columns and boxes + * which contain a number more than once. + */ + for (x = 0; x < cr * cr; x++) + ds->entered_items[x] = 0; + for (x = 0; x < cr; x++) + for (y = 0; y < cr; y++) { + digit d = state->grid[y*cr+x]; + if (d) { + int box = (x/r)+(y/c)*c; + ds->entered_items[x*cr+d-1] |= ((ds->entered_items[x*cr+d-1] & 1) << 1) | 1; + ds->entered_items[y*cr+d-1] |= ((ds->entered_items[y*cr+d-1] & 4) << 1) | 4; + ds->entered_items[box*cr+d-1] |= ((ds->entered_items[box*cr+d-1] & 16) << 1) | 16; + } + } + + /* * Draw any numbers which need redrawing. */ for (x = 0; x < cr; x++) { for (y = 0; y < cr; y++) { - draw_number(fe, ds, state, x, y, - (x == ui->hx && y == ui->hy) || - (flashtime > 0 && - (flashtime <= FLASH_TIME/3 || - flashtime >= FLASH_TIME*2/3))); + int highlight = 0; + digit d = state->grid[y*cr+x]; + + if (flashtime > 0 && + (flashtime <= FLASH_TIME/3 || + flashtime >= FLASH_TIME*2/3)) + highlight = 1; + + /* Highlight active input areas. */ + if (x == ui->hx && y == ui->hy) + highlight = ui->hpencil ? 2 : 1; + + /* Mark obvious errors (ie, numbers which occur more than once + * in a single row, column, or box). */ + if (d && ((ds->entered_items[x*cr+d-1] & 2) || + (ds->entered_items[y*cr+d-1] & 8) || + (ds->entered_items[((x/r)+(y/c)*c)*cr+d-1] & 32))) + highlight |= 16; + + draw_number(fe, ds, state, x, y, highlight); } } @@ -1858,21 +2538,22 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, * Update the _entire_ grid if necessary. */ if (!ds->started) { - draw_update(fe, 0, 0, XSIZE(cr), YSIZE(cr)); + draw_update(fe, 0, 0, SIZE(cr), SIZE(cr)); ds->started = TRUE; } } static float game_anim_length(game_state *oldstate, game_state *newstate, - int dir) + int dir, game_ui *ui) { return 0.0F; } static float game_flash_length(game_state *oldstate, game_state *newstate, - int dir) + int dir, game_ui *ui) { - if (!oldstate->completed && newstate->completed) + if (!oldstate->completed && newstate->completed && + !oldstate->cheated && !newstate->cheated) return FLASH_TIME; return 0.0F; } @@ -1882,6 +2563,11 @@ static int game_wants_statusbar(void) return FALSE; } +static int game_timing_state(game_state *state, game_ui *ui) +{ + return TRUE; +} + #ifdef COMBINED #define thegame solo #endif @@ -1896,15 +2582,21 @@ const struct game thegame = { dup_params, TRUE, game_configure, custom_params, validate_params, - new_game_seed, - validate_seed, + new_game_desc, + validate_desc, new_game, dup_game, free_game, + TRUE, solve_game, + TRUE, game_text_format, new_ui, free_ui, - make_move, - game_size, + encode_ui, + decode_ui, + game_changed_state, + interpret_move, + execute_move, + PREFERRED_TILE_SIZE, game_compute_size, game_set_size, game_colours, game_new_drawstate, game_free_drawstate, @@ -1912,6 +2604,8 @@ const struct game thegame = { game_anim_length, game_flash_length, game_wants_statusbar, + FALSE, game_timing_state, + 0, /* mouse_priorities */ }; #ifdef STANDALONE_SOLVER @@ -1926,7 +2620,7 @@ void draw_text(frontend *fe, int x, int y, int fonttype, int fontsize, void draw_rect(frontend *fe, int x, int y, int w, int h, int colour) {} void draw_line(frontend *fe, int x1, int y1, int x2, int y2, int colour) {} void draw_polygon(frontend *fe, int *coords, int npoints, - int fill, int colour) {} + int fillcolour, int outlinecolour) {} void clip(frontend *fe, int x, int y, int w, int h) {} void unclip(frontend *fe) {} void start_draw(frontend *fe) {} @@ -1936,6 +2630,8 @@ unsigned long random_bits(random_state *state, int bits) { assert(!"Shouldn't get randomness"); return 0; } unsigned long random_upto(random_state *state, unsigned long limit) { assert(!"Shouldn't get randomness"); return 0; } +void shuffle(void *array, int nelts, int eltsize, random_state *rs) +{ assert(!"Shouldn't get randomness"); } void fatal(char *fmt, ...) { @@ -1955,25 +2651,18 @@ int main(int argc, char **argv) { game_params *p; game_state *s; - int recurse = TRUE; - char *id = NULL, *seed, *err; - int y, x; + char *id = NULL, *desc, *err; int grade = FALSE; + int ret; while (--argc > 0) { char *p = *++argv; - if (!strcmp(p, "-r")) { - recurse = TRUE; - } else if (!strcmp(p, "-n")) { - recurse = FALSE; - } else if (!strcmp(p, "-v")) { + if (!strcmp(p, "-v")) { solver_show_working = TRUE; - recurse = FALSE; } else if (!strcmp(p, "-g")) { grade = TRUE; - recurse = FALSE; } else if (*p == '-') { - fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0]); + fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p); return 1; } else { id = p; @@ -1981,91 +2670,40 @@ int main(int argc, char **argv) } if (!id) { - fprintf(stderr, "usage: %s [-n | -r | -g | -v] \n", argv[0]); + fprintf(stderr, "usage: %s [-g | -v] \n", argv[0]); return 1; } - seed = strchr(id, ':'); - if (!seed) { + desc = strchr(id, ':'); + if (!desc) { fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); return 1; } - *seed++ = '\0'; + *desc++ = '\0'; - p = decode_params(id); - err = validate_seed(p, seed); + p = default_params(); + decode_params(p, id); + err = validate_desc(p, desc); if (err) { fprintf(stderr, "%s: %s\n", argv[0], err); return 1; } - s = new_game(p, seed); - - if (recurse) { - int ret = rsolve(p->c, p->r, s->grid, NULL, 2); - if (ret > 1) { - fprintf(stderr, "%s: rsolve: multiple solutions detected\n", - argv[0]); - } + s = new_game(NULL, p, desc); + + ret = solver(p->c, p->r, s->grid, DIFF_RECURSIVE); + if (grade) { + printf("Difficulty rating: %s\n", + ret==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)": + ret==DIFF_SIMPLE ? "Basic (row/column/number elimination required)": + ret==DIFF_INTERSECT ? "Intermediate (intersectional analysis required)": + ret==DIFF_SET ? "Advanced (set elimination required)": + ret==DIFF_RECURSIVE ? "Unreasonable (guesswork and backtracking required)": + ret==DIFF_AMBIGUOUS ? "Ambiguous (multiple solutions exist)": + ret==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)": + "INTERNAL ERROR: unrecognised difficulty code"); } else { - int ret = nsolve(p->c, p->r, s->grid); - if (grade) { - if (ret == DIFF_IMPOSSIBLE) { - /* - * Now resort to rsolve to determine whether it's - * really soluble. - */ - ret = rsolve(p->c, p->r, s->grid, NULL, 2); - if (ret == 0) - ret = DIFF_IMPOSSIBLE; - else if (ret == 1) - ret = DIFF_RECURSIVE; - else - ret = DIFF_AMBIGUOUS; - } - printf("Difficulty rating: %s\n", - ret==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)": - ret==DIFF_SIMPLE ? "Basic (row/column/number elimination required)": - ret==DIFF_INTERSECT ? "Intermediate (intersectional analysis required)": - ret==DIFF_SET ? "Advanced (set elimination required)": - ret==DIFF_RECURSIVE ? "Unreasonable (guesswork and backtracking required)": - ret==DIFF_AMBIGUOUS ? "Ambiguous (multiple solutions exist)": - ret==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)": - "INTERNAL ERROR: unrecognised difficulty code"); - } - } - - for (y = 0; y < p->c * p->r; y++) { - for (x = 0; x < p->c * p->r; x++) { - int c = s->grid[y * p->c * p->r + x]; - if (c == 0) - c = ' '; - else if (c <= 9) - c = '0' + c; - else - c = 'a' + c-10; - printf("%c", c); - if (x+1 < p->c * p->r) { - if ((x+1) % p->r) - printf(" "); - else - printf(" | "); - } - } - printf("\n"); - if (y+1 < p->c * p->r && (y+1) % p->c == 0) { - for (x = 0; x < p->c * p->r; x++) { - printf("-"); - if (x+1 < p->c * p->r) { - if ((x+1) % p->r) - printf("-"); - else - printf("-+-"); - } - } - printf("\n"); - } + printf("%s\n", grid_text_format(p->c, p->r, s->grid)); } - printf("\n"); return 0; }