X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/puzzles/blobdiff_plain/3a271e7ce1fafc749ff234beb8299753411a50e1..b84b31a86d91dd31623f842d47d63f6e51472cc7:/latin.c diff --git a/latin.c b/latin.c index 45096e4..a1117e0 100644 --- a/latin.c +++ b/latin.c @@ -16,6 +16,10 @@ * Solver. */ +#ifdef STANDALONE_SOLVER +int solver_show_working, solver_recurse_depth; +#endif + /* * Function called when we are certain that a particular square has * a particular number in it. The y-coordinate passed in here is @@ -100,7 +104,7 @@ int latin_solver_elim(struct latin_solver *solver, int start, int step vprintf(fmt, ap); va_end(ap); printf(":\n%*s placing %d at (%d,%d)\n", - solver_recurse_depth*4, "", n, x, YUNTRANS(y)); + solver_recurse_depth*4, "", n, x+1, YUNTRANS(y)+1); } #endif latin_solver_place(solver, x, y, n); @@ -290,7 +294,7 @@ int latin_solver_set(struct latin_solver *solver, printf("%*s ruling out %d at (%d,%d)\n", solver_recurse_depth*4, "", - pn, px, YUNTRANS(py)); + pn, px+1, YUNTRANS(py)+1); } #endif progress = TRUE; @@ -486,8 +490,8 @@ int latin_solver_forcing(struct latin_solver *solver, xl = xx; yl = yy; while (1) { - printf("%s(%d,%d)", sep, xl, - YUNTRANS(yl)); + printf("%s(%d,%d)", sep, xl+1, + YUNTRANS(yl)+1); xl = bfsprev[yl*o+xl]; if (xl < 0) break; @@ -497,7 +501,7 @@ int latin_solver_forcing(struct latin_solver *solver, } printf("\n%*s ruling out %d at (%d,%d)\n", solver_recurse_depth*4, "", - orign, xt, YUNTRANS(yt)); + orign, xt+1, YUNTRANS(yt)+1); } #endif cube(xt, yt, orign) = FALSE; @@ -580,7 +584,7 @@ int latin_solver_diff_simple(struct latin_solver *solver) ret = latin_solver_elim(solver, cubepos(0,y,n), o*o #ifdef STANDALONE_SOLVER , "positional elimination," - " %d in row %d", n, YUNTRANS(y) + " %d in row %d", n, YUNTRANS(y)+1 #endif ); if (ret != 0) return ret; @@ -594,7 +598,7 @@ int latin_solver_diff_simple(struct latin_solver *solver) ret = latin_solver_elim(solver, cubepos(x,0,n), o #ifdef STANDALONE_SOLVER , "positional elimination," - " %d in column %d", n, x + " %d in column %d", n, x+1 #endif ); if (ret != 0) return ret; @@ -608,8 +612,8 @@ int latin_solver_diff_simple(struct latin_solver *solver) if (!solver->grid[YUNTRANS(y)*o+x]) { ret = latin_solver_elim(solver, cubepos(x,y,1), 1 #ifdef STANDALONE_SOLVER - , "numeric elimination at (%d,%d)", x, - YUNTRANS(y) + , "numeric elimination at (%d,%d)", + x+1, YUNTRANS(y)+1 #endif ); if (ret != 0) return ret; @@ -630,7 +634,7 @@ int latin_solver_diff_set(struct latin_solver *solver, for (y = 0; y < o; y++) { ret = latin_solver_set(solver, scratch, cubepos(0,y,1), o*o, 1 #ifdef STANDALONE_SOLVER - , "set elimination, row %d", YUNTRANS(y) + , "set elimination, row %d", YUNTRANS(y)+1 #endif ); if (ret != 0) return ret; @@ -641,7 +645,7 @@ int latin_solver_diff_set(struct latin_solver *solver, for (x = 0; x < o; x++) { ret = latin_solver_set(solver, scratch, cubepos(x,0,1), o, 1 #ifdef STANDALONE_SOLVER - , "set elimination, column %d", x + , "set elimination, column %d", x+1 #endif ); if (ret != 0) return ret; @@ -663,11 +667,8 @@ int latin_solver_diff_set(struct latin_solver *solver, return 0; } -/* This uses our own diff_* internally, but doesn't require callers - * to; this is so it can be used by games that want to rewrite - * the solver so as to use a different set of difficulties. - * - * It returns: +/* + * Returns: * 0 for 'didn't do anything' implying it was already solved. * -1 for 'impossible' (no solution) * 1 for 'single solution' @@ -676,8 +677,11 @@ int latin_solver_diff_set(struct latin_solver *solver, * * and this function may well assert if given an impossible board. */ -int latin_solver_recurse(struct latin_solver *solver, int recdiff, - latin_solver_callback cb, void *ctx) +static int latin_solver_recurse + (struct latin_solver *solver, int diff_simple, int diff_set_0, + int diff_set_1, int diff_forcing, int diff_recursive, + usersolver_t const *usersolvers, void *ctx, + ctxnew_t ctxnew, ctxfree_t ctxfree) { int best, bestcount; int o = solver->o, x, y, n; @@ -739,7 +743,7 @@ int latin_solver_recurse(struct latin_solver *solver, int recdiff, if (solver_show_working) { char *sep = ""; printf("%*srecursing on (%d,%d) [", - solver_recurse_depth*4, "", x, y); + solver_recurse_depth*4, "", x+1, y+1); for (i = 0; i < j; i++) { printf("%s%d", sep, list[i]); sep = " or "; @@ -754,6 +758,7 @@ int latin_solver_recurse(struct latin_solver *solver, int recdiff, */ for (i = 0; i < j; i++) { int ret; + void *newctx; memcpy(outgrid, ingrid, o*o); outgrid[y*o+x] = list[i]; @@ -761,17 +766,27 @@ int latin_solver_recurse(struct latin_solver *solver, int recdiff, #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*4, "", list[i], x+1, y+1); solver_recurse_depth++; #endif - ret = cb(outgrid, o, recdiff, ctx); + if (ctxnew) { + newctx = ctxnew(ctx); + } else { + newctx = ctx; + } + ret = latin_solver(outgrid, o, diff_recursive, + diff_simple, diff_set_0, diff_set_1, + diff_forcing, diff_recursive, + usersolvers, newctx, ctxnew, ctxfree); + if (ctxnew) + ctxfree(newctx); #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); + solver_recurse_depth*4, "", list[i], x+1, y+1); } #endif /* we recurse as deep as we can, so we should never find @@ -793,7 +808,7 @@ int latin_solver_recurse(struct latin_solver *solver, int recdiff, else { /* the recursion turned up exactly one solution */ if (diff == diff_impossible) - diff = recdiff; + diff = diff_recursive; else diff = diff_ambiguous; } @@ -815,15 +830,17 @@ int latin_solver_recurse(struct latin_solver *solver, int recdiff, else if (diff == diff_ambiguous) return 2; else { - assert(diff == recdiff); + assert(diff == diff_recursive); return 1; } } } -enum { diff_simple = 1, diff_set, diff_extreme, diff_recursive }; - -static int latin_solver_sub(struct latin_solver *solver, int maxdiff, void *ctx) +int latin_solver_main(struct latin_solver *solver, int maxdiff, + int diff_simple, int diff_set_0, int diff_set_1, + int diff_forcing, int diff_recursive, + usersolver_t const *usersolvers, void *ctx, + ctxnew_t ctxnew, ctxfree_t ctxfree) { struct latin_solver_scratch *scratch = latin_solver_new_scratch(solver); int ret, diff = diff_simple; @@ -837,56 +854,34 @@ static int latin_solver_sub(struct latin_solver *solver, int maxdiff, void *ctx) * not. */ while (1) { - /* - * I'd like to write `continue;' inside each of the - * following loops, so that the solver returns here after - * making some progress. However, I can't specify that I - * want to continue an outer loop rather than the innermost - * one, so I'm apologetically resorting to a goto. - */ - cont: - latin_solver_debug(solver->cube, solver->o); - - ret = latin_solver_diff_simple(solver); - 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; - - ret = latin_solver_diff_set(solver, scratch, 0); - if (ret < 0) { - diff = diff_impossible; - goto got_result; - } else if (ret > 0) { - diff = max(diff, diff_set); - goto cont; - } + int i; - if (maxdiff <= diff_set) - break; + cont: - ret = latin_solver_diff_set(solver, scratch, 1); - if (ret < 0) { - diff = diff_impossible; - goto got_result; - } else if (ret > 0) { - diff = max(diff, diff_extreme); - goto cont; - } + latin_solver_debug(solver->cube, solver->o); - /* - * Forcing chains. - */ - if (latin_solver_forcing(solver, scratch)) { - diff = max(diff, diff_extreme); - goto cont; - } + for (i = 0; i <= maxdiff; i++) { + if (usersolvers[i]) + ret = usersolvers[i](solver, ctx); + else + ret = 0; + if (ret == 0 && i == diff_simple) + ret = latin_solver_diff_simple(solver); + if (ret == 0 && i == diff_set_0) + ret = latin_solver_diff_set(solver, scratch, 0); + if (ret == 0 && i == diff_set_1) + ret = latin_solver_diff_set(solver, scratch, 1); + if (ret == 0 && i == diff_forcing) + ret = latin_solver_forcing(solver, scratch); + + if (ret < 0) { + diff = diff_impossible; + goto got_result; + } else if (ret > 0) { + diff = max(diff, i); + goto cont; + } + } /* * If we reach here, we have made no deductions in this @@ -903,7 +898,10 @@ static int latin_solver_sub(struct latin_solver *solver, int maxdiff, void *ctx) * possible. */ if (maxdiff == diff_recursive) { - int nsol = latin_solver_recurse(solver, diff_recursive, latin_solver, ctx); + int nsol = latin_solver_recurse(solver, + diff_simple, diff_set_0, diff_set_1, + diff_forcing, diff_recursive, + usersolvers, ctx, ctxnew, ctxfree); if (nsol < 0) diff = diff_impossible; else if (nsol == 1) diff = diff_recursive; else if (nsol > 1) diff = diff_ambiguous; @@ -940,13 +938,20 @@ static int latin_solver_sub(struct latin_solver *solver, int maxdiff, void *ctx) return diff; } -int latin_solver(digit *grid, int o, int maxdiff, void *ctx) +int latin_solver(digit *grid, int o, int maxdiff, + int diff_simple, int diff_set_0, int diff_set_1, + int diff_forcing, int diff_recursive, + usersolver_t const *usersolvers, void *ctx, + ctxnew_t ctxnew, ctxfree_t ctxfree) { struct latin_solver solver; int diff; latin_solver_alloc(&solver, grid, o); - diff = latin_solver_sub(&solver, maxdiff, ctx); + diff = latin_solver_main(&solver, maxdiff, + diff_simple, diff_set_0, diff_set_1, + diff_forcing, diff_recursive, + usersolvers, ctx, ctxnew, ctxfree); latin_solver_free(&solver); return diff; } @@ -954,7 +959,7 @@ int latin_solver(digit *grid, int o, int maxdiff, void *ctx) void latin_solver_debug(unsigned char *cube, int o) { #ifdef STANDALONE_SOLVER - if (solver_show_working) { + if (solver_show_working > 1) { struct latin_solver ls, *solver = &ls; char *dbg; int x, y, i, c = 0;