--- /dev/null
+/*
+ * singles.c: implementation of Hitori ('let me alone') from Nikoli.
+ *
+ * Make single-get able to fetch a specific puzzle ID from menneske.no?
+ *
+ * www.menneske.no solving methods:
+ *
+ * Done:
+ * SC: if you circle a cell, any cells in same row/col with same no --> black
+ * -- solver_op_circle
+ * SB: if you make a cell black, any cells around it --> white
+ * -- solver_op_blacken
+ * ST: 3 identical cells in row, centre is white and outer two black.
+ * SP: 2 identical cells with single-cell gap, middle cell is white.
+ * -- solver_singlesep (both ST and SP)
+ * PI: if you have a pair of same number in row/col, any other
+ * cells of same number must be black.
+ * -- solve_doubles
+ * CC: if you have a black on edge one cell away from corner, cell
+ * on edge diag. adjacent must be white.
+ * CE: if you have 2 black cells of triangle on edge, third cell must
+ * be white.
+ * QM: if you have 3 black cells of diagonal square in middle, fourth
+ * cell must be white.
+ * -- solve_allblackbutone (CC, CE, and QM).
+ * QC: a corner with 4 identical numbers (or 2 and 2) must have the
+ * corner cell (and cell diagonal to that) black.
+ * TC: a corner with 3 identical numbers (with the L either way)
+ * must have the apex of L black, and other two white.
+ * DC: a corner with 2 identical numbers in domino can set a white
+ * cell along wall.
+ * -- solve_corners (QC, TC, DC)
+ * IP: pair with one-offset-pair force whites by offset pair
+ * -- solve_offsetpair
+ * MC: any cells diag. adjacent to black cells that would split board
+ * into separate white regions must be white.
+ * -- solve_removesplits
+ *
+ * Still to do:
+ *
+ * TEP: 3 pairs of dominos parallel to side, can mark 4 white cells
+ * alongside.
+ * DEP: 2 pairs of dominos parallel to side, can mark 2 white cells.
+ * FI: if you have two sets of double-cells packed together, singles
+ * in that row/col must be white (qv. PI)
+ * QuM: four identical cells (or 2 and 2) in middle of grid only have
+ * two possible solutions each.
+ * FDE: doubles one row/column away from edge can force a white cell.
+ * FDM: doubles in centre (next to bits of diag. square) can force a white cell.
+ * MP: two pairs with same number between force number to black.
+ * CnC: if circling a cell leads to impossible board, cell is black.
+ * MC: if we have two possiblilities, can we force a white circle?
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <ctype.h>
+#include <math.h>
+
+#include "puzzles.h"
+#include "latin.h"
+
+#ifdef STANDALONE_SOLVER
+int verbose = 0;
+#endif
+
+#define PREFERRED_TILE_SIZE 32
+#define TILE_SIZE (ds->tilesize)
+#define BORDER (TILE_SIZE / 2)
+
+#define CRAD ((TILE_SIZE / 2) - 1)
+#define TEXTSZ ((14*CRAD/10) - 1) /* 2 * sqrt(2) of CRAD */
+
+#define COORD(x) ( (x) * TILE_SIZE + BORDER )
+#define FROMCOORD(x) ( ((x) - BORDER + TILE_SIZE) / TILE_SIZE - 1 )
+
+#define INGRID(s,x,y) ((x) >= 0 && (x) < (s)->w && (y) >= 0 && (y) < (s)->h)
+
+#define FLASH_TIME 0.7F
+
+enum {
+ COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT,
+ COL_BLACK, COL_WHITE, COL_BLACKNUM, COL_GRID,
+ COL_CURSOR, COL_ERROR,
+ NCOLOURS
+};
+
+struct game_params {
+ int w, h, diff;
+};
+
+#define F_BLACK 0x1
+#define F_CIRCLE 0x2
+#define F_ERROR 0x4
+#define F_SCRATCH 0x8
+
+struct game_state {
+ int w, h, n, o; /* n = w*h; o = max(w, h) */
+ int completed, used_solve, impossible;
+ int *nums; /* size w*h */
+ unsigned int *flags; /* size w*h */
+};
+
+/* top, right, bottom, left */
+static const int dxs[4] = { 0, 1, 0, -1 };
+static const int dys[4] = { -1, 0, 1, 0 };
+
+/* --- Game parameters and preset functions --- */
+
+#define DIFFLIST(A) \
+ A(EASY,Easy,e) \
+ A(TRICKY,Tricky,k)
+
+#define ENUM(upper,title,lower) DIFF_ ## upper,
+#define TITLE(upper,title,lower) #title,
+#define ENCODE(upper,title,lower) #lower
+#define CONFIG(upper,title,lower) ":" #title
+
+enum { DIFFLIST(ENUM) DIFF_MAX, DIFF_ANY };
+static char const *const singles_diffnames[] = { DIFFLIST(TITLE) };
+static char const singles_diffchars[] = DIFFLIST(ENCODE);
+#define DIFFCOUNT lenof(singles_diffchars)
+#define DIFFCONFIG DIFFLIST(CONFIG)
+
+static game_params *default_params(void)
+{
+ game_params *ret = snew(game_params);
+ ret->w = ret->h = 5;
+ ret->diff = DIFF_EASY;
+
+ return ret;
+}
+
+static const struct game_params singles_presets[] = {
+ { 5, 5, DIFF_EASY },
+ { 5, 5, DIFF_TRICKY },
+ { 6, 6, DIFF_EASY },
+ { 6, 6, DIFF_TRICKY },
+ { 8, 8, DIFF_EASY },
+ { 8, 8, DIFF_TRICKY },
+ { 10, 10, DIFF_EASY },
+ { 10, 10, DIFF_TRICKY },
+ { 12, 12, DIFF_EASY },
+ { 12, 12, DIFF_TRICKY }
+};
+
+static int game_fetch_preset(int i, char **name, game_params **params)
+{
+ game_params *ret;
+ char buf[80];
+
+ if (i < 0 || i >= lenof(singles_presets))
+ return FALSE;
+
+ ret = default_params();
+ *ret = singles_presets[i];
+ *params = ret;
+
+ sprintf(buf, "%dx%d %s", ret->w, ret->h, singles_diffnames[ret->diff]);
+ *name = dupstr(buf);
+
+ return TRUE;
+}
+
+static void free_params(game_params *params)
+{
+ sfree(params);
+}
+
+static game_params *dup_params(game_params *params)
+{
+ game_params *ret = snew(game_params);
+ *ret = *params; /* structure copy */
+ return ret;
+}
+
+static void decode_params(game_params *ret, char const *string)
+{
+ char const *p = string;
+ int i;
+
+ ret->w = ret->h = atoi(p);
+ while (*p && isdigit((unsigned char)*p)) p++;
+ if (*p == 'x') {
+ p++;
+ ret->h = atoi(p);
+ while (*p && isdigit((unsigned char)*p)) p++;
+ }
+ if (*p == 'd') {
+ ret->diff = DIFF_MAX; /* which is invalid */
+ p++;
+ for (i = 0; i < DIFFCOUNT; i++) {
+ if (*p == singles_diffchars[i])
+ ret->diff = i;
+ }
+ p++;
+ }
+}
+
+static char *encode_params(game_params *params, int full)
+{
+ char data[256];
+
+ if (full)
+ sprintf(data, "%dx%dd%c", params->w, params->h, singles_diffchars[params->diff]);
+ else
+ sprintf(data, "%dx%d", params->w, params->h);
+
+ return dupstr(data);
+}
+
+static config_item *game_configure(game_params *params)
+{
+ config_item *ret;
+ char buf[80];
+
+ ret = snewn(4, config_item);
+
+ ret[0].name = "Width";
+ ret[0].type = C_STRING;
+ sprintf(buf, "%d", params->w);
+ ret[0].sval = dupstr(buf);
+ ret[0].ival = 0;
+
+ ret[1].name = "Height";
+ ret[1].type = C_STRING;
+ sprintf(buf, "%d", params->h);
+ ret[1].sval = dupstr(buf);
+ ret[1].ival = 0;
+
+ ret[2].name = "Difficulty";
+ ret[2].type = C_CHOICES;
+ ret[2].sval = DIFFCONFIG;
+ ret[2].ival = params->diff;
+
+ ret[3].name = NULL;
+ ret[3].type = C_END;
+ ret[3].sval = NULL;
+ ret[3].ival = 0;
+
+ return ret;
+}
+
+static game_params *custom_params(config_item *cfg)
+{
+ game_params *ret = snew(game_params);
+
+ ret->w = atoi(cfg[0].sval);
+ ret->h = atoi(cfg[1].sval);
+ ret->diff = cfg[2].ival;
+
+ return ret;
+}
+
+static char *validate_params(game_params *params, int full)
+{
+ if (params->w < 2 || params->h < 2)
+ return "Width and neight must be at least two";
+ if (params->w > 10+26+26 || params->h > 10+26+26)
+ return "Puzzle is too large";
+ if (full) {
+ if (params->diff < 0 || params->diff >= DIFF_MAX)
+ return "Unknown difficulty rating";
+ }
+
+ return NULL;
+}
+
+/* --- Game description string generation and unpicking --- */
+
+static game_state *blank_game(int w, int h)
+{
+ game_state *state = snew(game_state);
+
+ memset(state, 0, sizeof(game_state));
+ state->w = w;
+ state->h = h;
+ state->n = w*h;
+ state->o = max(w,h);
+
+ state->completed = state->used_solve = state->impossible = 0;
+
+ state->nums = snewn(state->n, int);
+ state->flags = snewn(state->n, unsigned int);
+
+ memset(state->nums, 0, state->n*sizeof(int));
+ memset(state->flags, 0, state->n*sizeof(unsigned int));
+
+ return state;
+}
+
+static game_state *dup_game(game_state *state)
+{
+ game_state *ret = blank_game(state->w, state->h);
+
+ ret->completed = state->completed;
+ ret->used_solve = state->used_solve;
+ ret->impossible = state->impossible;
+
+ memcpy(ret->nums, state->nums, state->n*sizeof(int));
+ memcpy(ret->flags, state->flags, state->n*sizeof(unsigned int));
+
+ return ret;
+}
+
+static void free_game(game_state *state)
+{
+ sfree(state->nums);
+ sfree(state->flags);
+ sfree(state);
+}
+
+static char n2c(int num) {
+ if (num < 10)
+ return '0' + num;
+ else if (num < 10+26)
+ return 'a' + num - 10;
+ else
+ return 'A' + num - 10 - 26;
+ return '?';
+}
+
+static int c2n(char c) {
+ if (isdigit(c))
+ return (int)(c - '0');
+ else if (c >= 'a' && c <= 'z')
+ return (int)(c - 'a' + 10);
+ else if (c >= 'A' && c <= 'Z')
+ return (int)(c - 'A' + 10 + 26);
+ return -1;
+}
+
+static void unpick_desc(game_params *params, char *desc,
+ game_state **sout, char **mout)
+{
+ game_state *state = blank_game(params->w, params->h);
+ char *msg = NULL;
+ int num = 0, i = 0;
+
+ if (strlen(desc) != state->n) {
+ msg = "Game description is wrong length";
+ goto done;
+ }
+ for (i = 0; i < state->n; i++) {
+ num = c2n(desc[i]);
+ if (num <= 0 || num > state->o) {
+ msg = "Game description contains unexpected characters";
+ goto done;
+ }
+ state->nums[i] = num;
+ }
+done:
+ if (msg) { /* sth went wrong. */
+ if (mout) *mout = msg;
+ free_game(state);
+ } else {
+ if (mout) *mout = NULL;
+ if (sout) *sout = state;
+ else free_game(state);
+ }
+}
+
+static char *generate_desc(game_state *state, int issolve)
+{
+ char *ret = snewn(state->n+1+(issolve?1:0), char);
+ int i, p=0;
+
+ if (issolve)
+ ret[p++] = 'S';
+ for (i = 0; i < state->n; i++)
+ ret[p++] = n2c(state->nums[i]);
+ ret[p] = '\0';
+ return ret;
+}
+
+/* --- Useful game functions (completion, etc.) --- */
+
+static int game_can_format_as_text_now(game_params *params)
+{
+ return TRUE;
+}
+
+static char *game_text_format(game_state *state)
+{
+ int len, x, y, i;
+ char *ret, *p;
+
+ len = (state->w)*2; /* one row ... */
+ len = len * (state->h*2); /* ... h rows, including gaps ... */
+ len += 1; /* ... final NL */
+ p = ret = snewn(len, char);
+
+ for (y = 0; y < state->h; y++) {
+ for (x = 0; x < state->w; x++) {
+ i = y*state->w + x;
+ if (x > 0) *p++ = ' ';
+ *p++ = (state->flags[i] & F_BLACK) ? '*' : n2c(state->nums[i]);
+ }
+ *p++ = '\n';
+ for (x = 0; x < state->w; x++) {
+ i = y*state->w + x;
+ if (x > 0) *p++ = ' ';
+ *p++ = (state->flags[i] & F_CIRCLE) ? '~' : ' ';
+ }
+ *p++ = '\n';
+ }
+ *p++ = '\0';
+ assert(p - ret == len);
+
+ return ret;
+}
+
+static void debug_state(const char *desc, game_state *state) {
+ char *dbg = game_text_format(state);
+ debug(("%s:\n%s", desc, dbg));
+ sfree(dbg);
+}
+
+static void connect_if_same(game_state *state, int *dsf, int i1, int i2)
+{
+ int c1, c2;
+
+ if ((state->flags[i1] & F_BLACK) != (state->flags[i2] & F_BLACK))
+ return;
+
+ c1 = dsf_canonify(dsf, i1);
+ c2 = dsf_canonify(dsf, i2);
+ dsf_merge(dsf, c1, c2);
+}
+
+static void connect_dsf(game_state *state, int *dsf)
+{
+ int x, y, i;
+
+ /* Construct a dsf array for connected blocks; connections
+ * tracked to right and down. */
+ dsf_init(dsf, state->n);
+ for (x = 0; x < state->w; x++) {
+ for (y = 0; y < state->h; y++) {
+ i = y*state->w + x;
+
+ if (x < state->w-1)
+ connect_if_same(state, dsf, i, i+1); /* right */
+ if (y < state->h-1)
+ connect_if_same(state, dsf, i, i+state->w); /* down */
+ }
+ }
+}
+
+static int check_rowcol(game_state *state, int starti, int di, int sz, int mark_errors)
+{
+ int nerr = 0, n, m, i, j;
+
+ /* if any circled numbers have identical non-circled numbers on
+ * same row/column, error (non-circled)
+ * if any circled numbers in same column are same number, highlight them.
+ * if any rows/columns have >1 of same number, not complete. */
+
+ for (n = 0, i = starti; n < sz; n++, i += di) {
+ if (state->flags[i] & F_BLACK) continue;
+ for (m = n+1, j = i+di; m < sz; m++, j += di) {
+ if (state->flags[j] & F_BLACK) continue;
+ if (state->nums[i] != state->nums[j]) continue;
+
+ nerr++; /* ok, we have two numbers the same in a row. */
+ if (!mark_errors) continue;
+
+ /* If we have two circles in the same row around
+ * two identical numbers, they are _both_ wrong. */
+ if ((state->flags[i] & F_CIRCLE) &&
+ (state->flags[j] & F_CIRCLE)) {
+ state->flags[i] |= F_ERROR;
+ state->flags[j] |= F_ERROR;
+ }
+ /* Otherwise, if we have a circle, any other identical
+ * numbers in that row are obviously wrong. We don't
+ * highlight this, however, since it makes the process
+ * of solving the puzzle too easy (you circle a number
+ * and it promptly tells you which numbers to blacken! */
+#if 0
+ else if (state->flags[i] & F_CIRCLE)
+ state->flags[j] |= F_ERROR;
+ else if (state->flags[j] & F_CIRCLE)
+ state->flags[i] |= F_ERROR;
+#endif
+ }
+ }
+ return nerr;
+}
+
+static int check_complete(game_state *state, int mark_errors)
+{
+ int *dsf = snewn(state->n, int);
+ int x, y, i, error = 0, nwhite, w = state->w, h = state->h;
+
+ if (mark_errors) {
+ for (i = 0; i < state->n; i++)
+ state->flags[i] &= ~F_ERROR;
+ }
+ connect_dsf(state, dsf);
+
+ /* Mark any black squares in groups of >1 as errors.
+ * Count number of white squares. */
+ nwhite = 0;
+ for (i = 0; i < state->n; i++) {
+ if (state->flags[i] & F_BLACK) {
+ if (dsf_size(dsf, i) > 1) {
+ error += 1;
+ if (mark_errors)
+ state->flags[i] |= F_ERROR;
+ }
+ } else
+ nwhite += 1;
+ }
+
+ /* Check attributes of white squares, row- and column-wise. */
+ for (x = 0; x < w; x++) /* check cols from (x,0) */
+ error += check_rowcol(state, x, w, h, mark_errors);
+ for (y = 0; y < h; y++) /* check rows from (0,y) */
+ error += check_rowcol(state, y*w, 1, w, mark_errors);
+
+ /* mark (all) white regions as an error if there is more than one.
+ * may want to make this less in-your-face (by only marking
+ * the smallest region as an error, for example -- but what if we
+ * have two regions of identical size?) */
+ for (i = 0; i < state->n; i++) {
+ if (!(state->flags[i] & F_BLACK) &&
+ dsf_size(dsf, i) < nwhite) {
+ error += 1;
+ if (mark_errors)
+ state->flags[i] |= F_ERROR;
+ }
+ }
+
+ sfree(dsf);
+ return (error > 0) ? 0 : 1;
+}
+
+static char *game_state_diff(game_state *src, game_state *dst, int issolve)
+{
+ char *ret = NULL, buf[80], c;
+ int retlen = 0, x, y, i, k;
+ unsigned int fmask = F_BLACK | F_CIRCLE;
+
+ assert(src->n == dst->n);
+
+ if (issolve) {
+ ret = sresize(ret, 3, char);
+ ret[0] = 'S'; ret[1] = ';'; ret[2] = '\0';
+ retlen += 2;
+ }
+
+ for (x = 0; x < dst->w; x++) {
+ for (y = 0; y < dst->h; y++) {
+ i = y*dst->w + x;
+ if ((src->flags[i] & fmask) != (dst->flags[i] & fmask)) {
+ assert((dst->flags[i] & fmask) != fmask);
+ if (dst->flags[i] & F_BLACK)
+ c = 'B';
+ else if (dst->flags[i] & F_CIRCLE)
+ c = 'C';
+ else
+ c = 'E';
+ k = sprintf(buf, "%c%d,%d;", (int)c, x, y);
+ ret = sresize(ret, retlen + k + 1, char);
+ strcpy(ret + retlen, buf);
+ retlen += k;
+ }
+ }
+ }
+ return ret;
+}
+
+/* --- Solver --- */
+
+enum { BLACK, CIRCLE };
+
+struct solver_op {
+ int x, y, op; /* op one of BLACK or CIRCLE. */
+ const char *desc; /* must be non-malloced. */
+};
+
+struct solver_state {
+ struct solver_op *ops;
+ int n_ops, n_alloc;
+ int *scratch;
+};
+
+static struct solver_state *solver_state_new(game_state *state)
+{
+ struct solver_state *ss = snew(struct solver_state);
+
+ ss->ops = NULL;
+ ss->n_ops = ss->n_alloc = 0;
+ ss->scratch = snewn(state->n, int);
+
+ return ss;
+}
+
+static void solver_state_free(struct solver_state *ss)
+{
+ sfree(ss->scratch);
+ if (ss->ops) sfree(ss->ops);
+ sfree(ss);
+}
+
+static void solver_op_add(struct solver_state *ss, int x, int y, int op, const char *desc)
+{
+ struct solver_op *sop;
+
+ if (ss->n_alloc < ss->n_ops + 1) {
+ ss->n_alloc = (ss->n_alloc + 1) * 2;
+ ss->ops = sresize(ss->ops, ss->n_alloc, struct solver_op);
+ }
+ sop = &(ss->ops[ss->n_ops++]);
+ sop->x = x; sop->y = y; sop->op = op; sop->desc = desc;
+ debug(("added solver op %s ('%s') at (%d,%d)",
+ op == BLACK ? "BLACK" : "CIRCLE", desc, x, y));
+}
+
+static void solver_op_circle(game_state *state, struct solver_state *ss,
+ int x, int y)
+{
+ int i = y*state->w + x;
+
+ if (!INGRID(state, x, y)) return;
+ if (state->flags[i] & F_BLACK) {
+ debug(("... solver wants to add auto-circle on black (%d,%d)", x, y));
+ state->impossible = 1;
+ return;
+ }
+ /* Only add circle op if it's not already circled. */
+ if (!(state->flags[i] & F_CIRCLE)) {
+ solver_op_add(ss, x, y, CIRCLE, "SB - adjacent to black square");
+ }
+}
+
+static void solver_op_blacken(game_state *state, struct solver_state *ss,
+ int x, int y, int num)
+{
+ int i = y*state->w + x;
+
+ if (!INGRID(state, x, y)) return;
+ if (state->nums[i] != num) return;
+ if (state->flags[i] & F_CIRCLE) {
+ debug(("... solver wants to add auto-black on circled(%d,%d)", x, y));
+ state->impossible = 1;
+ return;
+ }
+ /* Only add black op if it's not already black. */
+ if (!(state->flags[i] & F_BLACK)) {
+ solver_op_add(ss, x, y, BLACK, "SC - number on same row/col as circled");
+ }
+}
+
+static int solver_ops_do(game_state *state, struct solver_state *ss)
+{
+ int next_op = 0, i, x, y, n_ops = 0;
+ struct solver_op op;
+
+ /* Care here: solver_op_* may call solver_op_add which may extend the
+ * ss->n_ops. */
+
+ while (next_op < ss->n_ops) {
+ op = ss->ops[next_op++]; /* copy this away, it may get reallocated. */
+ i = op.y*state->w + op.x;
+
+ if (op.op == BLACK) {
+ if (state->flags[i] & F_CIRCLE) {
+ debug(("Solver wants to blacken circled square (%d,%d)!", op.x, op.y));
+ state->impossible = 1;
+ return n_ops;
+ }
+ if (!(state->flags[i] & F_BLACK)) {
+ debug(("... solver adding black at (%d,%d): %s", op.x, op.y, op.desc));
+#ifdef STANDALONE_SOLVER
+ if (verbose)
+ printf("Adding black at (%d,%d): %s\n", op.x, op.y, op.desc);
+#endif
+ state->flags[i] |= F_BLACK;
+ /*debug_state("State after adding black", state);*/
+ n_ops++;
+ solver_op_circle(state, ss, op.x-1, op.y);
+ solver_op_circle(state, ss, op.x+1, op.y);
+ solver_op_circle(state, ss, op.x, op.y-1);
+ solver_op_circle(state, ss, op.x, op.y+1);
+ }
+ } else {
+ if (state->flags[i] & F_BLACK) {
+ debug(("Solver wants to circle blackened square (%d,%d)!", op.x, op.y));
+ state->impossible = 1;
+ return n_ops;
+ }
+ if (!(state->flags[i] & F_CIRCLE)) {
+ debug(("... solver adding circle at (%d,%d): %s", op.x, op.y, op.desc));
+#ifdef STANDALONE_SOLVER
+ if (verbose)
+ printf("Adding circle at (%d,%d): %s\n", op.x, op.y, op.desc);
+#endif
+ state->flags[i] |= F_CIRCLE;
+ /*debug_state("State after adding circle", state);*/
+ n_ops++;
+ for (x = 0; x < state->w; x++) {
+ if (x != op.x)
+ solver_op_blacken(state, ss, x, op.y, state->nums[i]);
+ }
+ for (y = 0; y < state->h; y++) {
+ if (y != op.y)
+ solver_op_blacken(state, ss, op.x, y, state->nums[i]);
+ }
+ }
+ }
+ }
+ ss->n_ops = 0;
+ return n_ops;
+}
+
+/* If the grid has two identical numbers with one cell between them, the inner
+ * cell _must_ be white (and thus circled); (at least) one of the two must be
+ * black (since they're in the same column or row) and thus the middle cell is
+ * next to a black cell. */
+static int solve_singlesep(game_state *state, struct solver_state *ss)
+{
+ int x, y, i, ir, irr, id, idd, n_ops = ss->n_ops;
+
+ for (x = 0; x < state->w; x++) {
+ for (y = 0; y < state->h; y++) {
+ i = y*state->w + x;
+
+ /* Cell two to our right? */
+ ir = i + 1; irr = ir + 1;
+ if (x < (state->w-2) &&
+ state->nums[i] == state->nums[irr] &&
+ !(state->flags[ir] & F_CIRCLE)) {
+ solver_op_add(ss, x+1, y, CIRCLE, "SP/ST - between identical nums");
+ }
+ /* Cell two below us? */
+ id = i + state->w; idd = id + state->w;
+ if (y < (state->h-2) &&
+ state->nums[i] == state->nums[idd] &&
+ !(state->flags[id] & F_CIRCLE)) {
+ solver_op_add(ss, x, y+1, CIRCLE, "SP/ST - between identical nums");
+ }
+ }
+ }
+ return ss->n_ops - n_ops;
+}
+
+/* If we have two identical numbers next to each other (in a row or column),
+ * any other identical numbers in that column must be black. */
+static int solve_doubles(game_state *state, struct solver_state *ss)
+{
+ int x, y, i, ii, n_ops = ss->n_ops, xy;
+
+ for (y = 0, i = 0; y < state->h; y++) {
+ for (x = 0; x < state->w; x++, i++) {
+ assert(i == y*state->w+x);
+ if (state->flags[i] & F_BLACK) continue;
+
+ ii = i+1; /* check cell to our right. */
+ if (x < (state->w-1) &&
+ !(state->flags[ii] & F_BLACK) &&
+ state->nums[i] == state->nums[ii]) {
+ for (xy = 0; xy < state->w; xy++) {
+ if (xy == x || xy == (x+1)) continue;
+ if (state->nums[y*state->w + xy] == state->nums[i] &&
+ !(state->flags[y*state->w + xy] & F_BLACK))
+ solver_op_add(ss, xy, y, BLACK, "PI - same row as pair");
+ }
+ }
+
+ ii = i+state->w; /* check cell below us */
+ if (y < (state->h-1) &&
+ !(state->flags[ii] & F_BLACK) &&
+ state->nums[i] == state->nums[ii]) {
+ for (xy = 0; xy < state->h; xy++) {
+ if (xy == y || xy == (y+1)) continue;
+ if (state->nums[xy*state->w + x] == state->nums[i] &&
+ !(state->flags[xy*state->w + x] & F_BLACK))
+ solver_op_add(ss, x, xy, BLACK, "PI - same col as pair");
+ }
+ }
+ }
+ }
+ return ss->n_ops - n_ops;
+}
+
+/* If a white square has all-but-one possible adjacent squares black, the
+ * one square left over must be white. */
+static int solve_allblackbutone(game_state *state, struct solver_state *ss)
+{
+ int x, y, i, n_ops = ss->n_ops, xd, yd, id, ifree;
+ int dis[4], d;
+
+ dis[0] = -state->w;
+ dis[1] = 1;
+ dis[2] = state->w;
+ dis[3] = -1;
+
+ for (y = 0, i = 0; y < state->h; y++) {
+ for (x = 0; x < state->w; x++, i++) {
+ assert(i == y*state->w+x);
+ if (state->flags[i] & F_BLACK) continue;
+
+ ifree = -1;
+ for (d = 0; d < 4; d++) {
+ xd = x + dxs[d]; yd = y + dys[d]; id = i + dis[d];
+ if (!INGRID(state, xd, yd)) continue;
+
+ if (state->flags[id] & F_CIRCLE)
+ goto skip; /* this cell already has a way out */
+ if (!(state->flags[id] & F_BLACK)) {
+ if (ifree != -1)
+ goto skip; /* this cell has >1 white cell around it. */
+ ifree = id;
+ }
+ }
+ if (ifree != -1)
+ solver_op_add(ss, ifree%state->w, ifree/state->w, CIRCLE,
+ "CC/CE/QM: white cell with single non-black around it");
+ else {
+ debug(("White cell with no escape at (%d,%d)", x, y));
+ state->impossible = 1;
+ return 0;
+ }
+skip: ;
+ }
+ }
+ return ss->n_ops - n_ops;
+}
+
+/* If we have 4 numbers the same in a 2x2 corner, the far corner and the
+ * diagonally-adjacent square must both be black.
+ * If we have 3 numbers the same in a 2x2 corner, the apex of the L
+ * thus formed must be black.
+ * If we have 2 numbers the same in a 2x2 corner, the non-same cell
+ * one away from the corner must be white. */
+static void solve_corner(game_state *state, struct solver_state *ss,
+ int x, int y, int dx, int dy)
+{
+ int is[4], ns[4], xx, yy, w = state->w;
+
+ for (yy = 0; yy < 2; yy++) {
+ for (xx = 0; xx < 2; xx++) {
+ is[yy*2+xx] = (y + dy*yy) * w + (x + dx*xx);
+ ns[yy*2+xx] = state->nums[is[yy*2+xx]];
+ }
+ } /* order is now (corner, side 1, side 2, inner) */
+
+ if (ns[0] == ns[1] && ns[0] == ns[2] && ns[0] == ns[3]) {
+ solver_op_add(ss, is[0]%w, is[0]/w, BLACK, "QC: corner with 4 matching");
+ solver_op_add(ss, is[3]%w, is[3]/w, BLACK, "QC: corner with 4 matching");
+ } else if (ns[0] == ns[1] && ns[0] == ns[2]) {
+ /* corner and 2 sides: apex is corner. */
+ solver_op_add(ss, is[0]%w, is[0]/w, BLACK, "TC: corner apex from 3 matching");
+ } else if (ns[1] == ns[2] && ns[1] == ns[3]) {
+ /* side, side, fourth: apex is fourth. */
+ solver_op_add(ss, is[3]%w, is[3]/w, BLACK, "TC: inside apex from 3 matching");
+ } else if (ns[0] == ns[1] || ns[1] == ns[3]) {
+ /* either way here we match the non-identical side. */
+ solver_op_add(ss, is[2]%w, is[2]/w, CIRCLE, "DC: corner with 2 matching");
+ } else if (ns[0] == ns[2] || ns[2] == ns[3]) {
+ /* ditto */
+ solver_op_add(ss, is[1]%w, is[1]/w, CIRCLE, "DC: corner with 2 matching");
+ }
+}
+
+static int solve_corners(game_state *state, struct solver_state *ss)
+{
+ int n_ops = ss->n_ops;
+
+ solve_corner(state, ss, 0, 0, 1, 1);
+ solve_corner(state, ss, state->w-1, 0, -1, 1);
+ solve_corner(state, ss, state->w-1, state->h-1, -1, -1);
+ solve_corner(state, ss, 0, state->h-1, 1, -1);
+
+ return ss->n_ops - n_ops;
+}
+
+/* If you have the following situation:
+ * ...
+ * ...x A x x y A x...
+ * ...x B x x B y x...
+ * ...
+ * then both squares marked 'y' must be white. One of the left-most A or B must
+ * be white (since two side-by-side black cells are disallowed), which means
+ * that the corresponding right-most A or B must be black (since you can't
+ * have two of the same number on one line); thus, the adjacent squares
+ * to that right-most A or B must be white, which include the two marked 'y'
+ * in either case.
+ * Obviously this works in any row or column. It also works if A == B.
+ * It doesn't work for the degenerate case:
+ * ...x A A x x
+ * ...x B y x x
+ * where the square marked 'y' isn't necessarily white (consider the left-most A
+ * is black).
+ *
+ * */
+static void solve_offsetpair_pair(game_state *state, struct solver_state *ss,
+ int x1, int y1, int x2, int y2)
+{
+ int ox, oy, w = state->w, ax, ay, an, d, dx[2], dy[2], dn, xd, yd;
+
+ if (x1 == x2) { /* same column */
+ ox = 1; oy = 0;
+ } else {
+ assert(y1 == y2);
+ ox = 0; oy = 1;
+ }
+
+ /* We try adjacent to (x1,y1) and the two diag. adjacent to (x2, y2).
+ * We expect to be called twice, once each way around. */
+ ax = x1+ox; ay = y1+oy;
+ assert(INGRID(state, ax, ay));
+ an = state->nums[ay*w + ax];
+
+ dx[0] = x2 + ox + oy; dx[1] = x2 + ox - oy;
+ dy[0] = y2 + oy + ox; dy[1] = y2 + oy - ox;
+
+ for (d = 0; d < 2; d++) {
+ if (INGRID(state, dx[d], dy[d]) && (dx[d] != ax || dy[d] != ay)) {
+ /* The 'dx != ax || dy != ay' removes the degenerate case,
+ * mentioned above. */
+ dn = state->nums[dy[d]*w + dx[d]];
+ if (an == dn) {
+ /* We have a match; so (WLOG) the 'A' marked above are at
+ * (x1,y1) and (x2,y2), and the 'B' are at (ax,ay) and (dx,dy). */
+ debug(("Found offset-pair: %d at (%d,%d) and (%d,%d)",
+ state->nums[y1*w + x1], x1, y1, x2, y2));
+ debug((" and: %d at (%d,%d) and (%d,%d)",
+ an, ax, ay, dx[d], dy[d]));
+
+ xd = dx[d] - x2; yd = dy[d] - y2;
+ solver_op_add(ss, x2 + xd, y2, CIRCLE, "IP: next to offset-pair");
+ solver_op_add(ss, x2, y2 + yd, CIRCLE, "IP: next to offset-pair");
+ }
+ }
+ }
+}
+
+static int solve_offsetpair(game_state *state, struct solver_state *ss)
+{
+ int n_ops = ss->n_ops, x, xx, y, yy, n1, n2;
+
+ for (x = 0; x < state->w-1; x++) {
+ for (y = 0; y < state->h; y++) {
+ n1 = state->nums[y*state->w + x];
+ for (yy = y+1; yy < state->h; yy++) {
+ n2 = state->nums[yy*state->w + x];
+ if (n1 == n2) {
+ solve_offsetpair_pair(state, ss, x, y, x, yy);
+ solve_offsetpair_pair(state, ss, x, yy, x, y);
+ }
+ }
+ }
+ }
+ for (y = 0; y < state->h-1; y++) {
+ for (x = 0; x < state->w; x++) {
+ n1 = state->nums[y*state->w + x];
+ for (xx = x+1; xx < state->w; xx++) {
+ n2 = state->nums[y*state->w + xx];
+ if (n1 == n2) {
+ solve_offsetpair_pair(state, ss, x, y, xx, y);
+ solve_offsetpair_pair(state, ss, xx, y, x, y);
+ }
+ }
+ }
+ }
+ return ss->n_ops - n_ops;
+}
+
+static int solve_hassinglewhiteregion(game_state *state, struct solver_state *ss)
+{
+ int i, j, nwhite = 0, lwhite = -1, szwhite, start, end, next, a, d, x, y;
+
+ for (i = 0; i < state->n; i++) {
+ if (!(state->flags[i] & F_BLACK)) {
+ nwhite++;
+ lwhite = i;
+ }
+ state->flags[i] &= ~F_SCRATCH;
+ }
+ if (lwhite == -1) {
+ debug(("solve_hassinglewhite: no white squares found!"));
+ state->impossible = 1;
+ return 0;
+ }
+ /* We don't use connect_dsf here; it's too slow, and there's a quicker
+ * algorithm if all we want is the size of one region. */
+ /* Having written this, this algorithm is only about 5% faster than
+ * using a dsf. */
+ memset(ss->scratch, -1, state->n * sizeof(int));
+ ss->scratch[0] = lwhite;
+ state->flags[lwhite] |= F_SCRATCH;
+ start = 0; end = next = 1;
+ while (start < end) {
+ for (a = start; a < end; a++) {
+ i = ss->scratch[a]; assert(i != -1);
+ for (d = 0; d < 4; d++) {
+ x = (i % state->w) + dxs[d];
+ y = (i / state->w) + dys[d];
+ j = y*state->w + x;
+ if (!INGRID(state, x, y)) continue;
+ if (state->flags[j] & (F_BLACK | F_SCRATCH)) continue;
+ ss->scratch[next++] = j;
+ state->flags[j] |= F_SCRATCH;
+ }
+ }
+ start = end; end = next;
+ }
+ szwhite = next;
+ return (szwhite == nwhite) ? 1 : 0;
+}
+
+static void solve_removesplits_check(game_state *state, struct solver_state *ss,
+ int x, int y)
+{
+ int i = y*state->w + x, issingle;
+
+ if (!INGRID(state, x, y)) return;
+ if ((state->flags[i] & F_CIRCLE) || (state->flags[i] & F_BLACK))
+ return;
+
+ /* If putting a black square at (x,y) would make the white region
+ * non-contiguous, it must be circled. */
+ state->flags[i] |= F_BLACK;
+ issingle = solve_hassinglewhiteregion(state, ss);
+ state->flags[i] &= ~F_BLACK;
+
+ if (!issingle)
+ solver_op_add(ss, x, y, CIRCLE, "MC: black square here would split white region");
+}
+
+/* For all black squares, search in squares diagonally adjacent to see if
+ * we can rule out putting a black square there (because it would make the
+ * white region non-contiguous). */
+/* This function is likely to be somewhat slow. */
+static int solve_removesplits(game_state *state, struct solver_state *ss)
+{
+ int i, x, y, n_ops = ss->n_ops;
+
+ if (!solve_hassinglewhiteregion(state, ss)) {
+ debug(("solve_removesplits: white region is not contiguous at start!"));
+ state->impossible = 1;
+ return 0;
+ }
+
+ for (i = 0; i < state->n; i++) {
+ if (!(state->flags[i] & F_BLACK)) continue;
+
+ x = i%state->w; y = i/state->w;
+ solve_removesplits_check(state, ss, x-1, y-1);
+ solve_removesplits_check(state, ss, x+1, y-1);
+ solve_removesplits_check(state, ss, x+1, y+1);
+ solve_removesplits_check(state, ss, x-1, y+1);
+ }
+ return ss->n_ops - n_ops;
+}
+
+/*
+ * This function performs a solver step that isn't implicit in the rules
+ * of the game and is thus treated somewhat differently.
+ *
+ * It marks cells whose number does not exist elsewhere in its row/column
+ * with circles. As it happens the game generator here does mean that this
+ * is always correct, but it's a solving method that people should not have
+ * to rely upon (except in the hidden 'sneaky' difficulty setting) and so
+ * all grids at 'tricky' and above are checked to make sure that the grid
+ * is no easier if this solving step is performed beforehand.
+ *
+ * Calling with ss=NULL just returns the number of sneaky deductions that
+ * would have been made.
+ */
+static int solve_sneaky(game_state *state, struct solver_state *ss)
+{
+ int i, ii, x, xx, y, yy, nunique = 0;
+
+ /* Clear SCRATCH flags. */
+ for (i = 0; i < state->n; i++) state->flags[i] &= ~F_SCRATCH;
+
+ for (x = 0; x < state->w; x++) {
+ for (y = 0; y < state->h; y++) {
+ i = y*state->w + x;
+
+ /* Check for duplicate numbers on our row, mark (both) if so */
+ for (xx = x; xx < state->w; xx++) {
+ ii = y*state->w + xx;
+ if (i == ii) continue;
+
+ if (state->nums[i] == state->nums[ii]) {
+ state->flags[i] |= F_SCRATCH;
+ state->flags[ii] |= F_SCRATCH;
+ }
+ }
+
+ /* Check for duplicate numbers on our col, mark (both) if so */
+ for (yy = y; yy < state->h; yy++) {
+ ii = yy*state->w + x;
+ if (i == ii) continue;
+
+ if (state->nums[i] == state->nums[ii]) {
+ state->flags[i] |= F_SCRATCH;
+ state->flags[ii] |= F_SCRATCH;
+ }
+ }
+ }
+ }
+
+ /* Any cell with no marking has no duplicates on its row or column:
+ * set its CIRCLE. */
+ for (i = 0; i < state->n; i++) {
+ if (!(state->flags[i] & F_SCRATCH)) {
+ if (ss) solver_op_add(ss, i%state->w, i/state->w, CIRCLE,
+ "SNEAKY: only one of its number in row and col");
+ nunique += 1;
+ } else
+ state->flags[i] &= ~F_SCRATCH;
+ }
+ return nunique;
+}
+
+static int solve_specific(game_state *state, int diff, int sneaky)
+{
+ struct solver_state *ss = solver_state_new(state);
+
+ if (sneaky) solve_sneaky(state, ss);
+
+ /* Some solver operations we only have to perform once --
+ * they're only based on the numbers available, and not black
+ * squares or circles which may be added later. */
+
+ solve_singlesep(state, ss); /* never sets impossible */
+ solve_doubles(state, ss); /* ditto */
+ solve_corners(state, ss); /* ditto */
+
+ if (diff >= DIFF_TRICKY)
+ solve_offsetpair(state, ss); /* ditto */
+
+ while (1) {
+ if (ss->n_ops > 0) solver_ops_do(state, ss);
+ if (state->impossible) break;
+
+ if (solve_allblackbutone(state, ss) > 0) continue;
+ if (state->impossible) break;
+
+ if (diff >= DIFF_TRICKY) {
+ if (solve_removesplits(state, ss) > 0) continue;
+ if (state->impossible) break;
+ }
+
+ break;
+ }
+
+ solver_state_free(ss);
+ return state->impossible ? -1 : check_complete(state, 0);
+}
+
+static char *solve_game(game_state *state, game_state *currstate,
+ char *aux, char **error)
+{
+ game_state *solved = dup_game(currstate);
+ char *move = NULL;
+
+ if (solve_specific(solved, DIFF_ANY, 0)) goto solved;
+ free_game(solved);
+
+ solved = dup_game(state);
+ if (solve_specific(solved, DIFF_ANY, 0)) goto solved;
+ free_game(solved);
+
+ *error = "Unable to solve puzzle.";
+ return NULL;
+
+solved:
+ move = game_state_diff(currstate, solved, 1);
+ free_game(solved);
+ return move;
+}
+
+/* --- Game generation --- */
+
+/* A correctly completed Hitori board is essentially a latin square
+ * (no duplicated numbers in any row or column) with black squares
+ * added such that no black square touches another, and the white
+ * squares make a contiguous region.
+ *
+ * So we can generate it by:
+ * constructing a latin square
+ * adding black squares at random (minding the constraints)
+ * altering the numbers under the new black squares such that
+ the solver gets a headstart working out where they are.
+ */
+
+static int new_game_is_good(game_params *params,
+ game_state *state, game_state *tosolve)
+{
+ int sret, sret_easy = 0;
+
+ memcpy(tosolve->nums, state->nums, state->n * sizeof(int));
+ memset(tosolve->flags, 0, state->n * sizeof(unsigned int));
+ tosolve->completed = tosolve->impossible = 0;
+
+ /*
+ * We try and solve it twice, once at our requested difficulty level
+ * (ensuring it's soluble at all) and once at the level below (if
+ * it exists), which we hope to fail: if you can also solve it at
+ * the level below then it's too easy and we have to try again.
+ *
+ * With this puzzle in particular there's an extra finesse, which is
+ * that we check that the generated puzzle isn't too easy _with
+ * an extra solver step first_, which is the 'sneaky' mode of deductions
+ * (asserting that any number which fulfils the latin-square rules
+ * on its row/column must be white). This is an artefact of the
+ * generation process and not implicit in the rules, so we don't want
+ * people to be able to use it to make the puzzle easier.
+ */
+
+ assert(params->diff < DIFF_MAX);
+ sret = solve_specific(tosolve, params->diff, 0);
+ if (params->diff > DIFF_EASY) {
+ memset(tosolve->flags, 0, state->n * sizeof(unsigned int));
+ tosolve->completed = tosolve->impossible = 0;
+
+ /* this is the only time the 'sneaky' flag is set to 1. */
+ sret_easy = solve_specific(tosolve, params->diff-1, 1);
+ }
+
+ if (sret <= 0 || sret_easy > 0) {
+ debug(("Generated puzzle %s at chosen difficulty %s",
+ sret <= 0 ? "insoluble" : "too easy",
+ singles_diffnames[params->diff]));
+ return 0;
+ }
+ return 1;
+}
+
+#define MAXTRIES 20
+
+static int best_black_col(game_state *state, random_state *rs, int *scratch,
+ int i, int *rownums, int *colnums)
+{
+ int w = state->w, x = i%w, y = i/w, j, o = state->o;
+
+ /* Randomise the list of numbers to try. */
+ for (i = 0; i < o; i++) scratch[i] = i;
+ shuffle(scratch, o, sizeof(int), rs);
+
+ /* Try each number in turn, first giving preference to removing
+ * latin-square characteristics (i.e. those numbers which only
+ * occur once in a row/column). The '&&' here, although intuitively
+ * wrong, results in a smaller number of 'sneaky' deductions on
+ * solvable boards. */
+ for (i = 0; i < o; i++) {
+ j = scratch[i] + 1;
+ if (rownums[y*o + j-1] == 1 && colnums[x*o + j-1] == 1)
+ return j;
+ }
+
+ /* Then try each number in turn returning the first one that's
+ * not actually unique in its row/column (see comment below) */
+ for (i = 0; i < o; i++) {
+ j = scratch[i] + 1;
+ if (rownums[y*o + j-1] != 0 || colnums[x*o + j-1] != 0)
+ return j;
+ }
+ assert(!"unable to place number under black cell.");
+ return 0;
+}
+
+static char *new_game_desc(game_params *params, random_state *rs,
+ char **aux, int interactive)
+{
+ game_state *state = blank_game(params->w, params->h);
+ game_state *tosolve = blank_game(params->w, params->h);
+ int i, j, *scratch, *rownums, *colnums, x, y, ntries;
+ int w = state->w, h = state->h, o = state->o;
+ char *ret;
+ digit *latin;
+ struct solver_state *ss = solver_state_new(state);
+
+ scratch = snewn(state->n, int);
+ rownums = snewn(h*o, int);
+ colnums = snewn(w*o, int);
+
+generate:
+ ss->n_ops = 0;
+ debug(("Starting game generation, size %dx%d", w, h));
+
+ memset(state->flags, 0, state->n*sizeof(unsigned int));
+
+ /* First, generate the latin rectangle.
+ * The order of this, o, is max(w,h). */
+ latin = latin_generate_rect(w, h, rs);
+ for (i = 0; i < state->n; i++)
+ state->nums[i] = (int)latin[i];
+ sfree(latin);
+ debug_state("State after latin square", state);
+
+ /* Add black squares at random, using bits of solver as we go (to lay
+ * white squares), until we can lay no more blacks. */
+ for (i = 0; i < state->n; i++)
+ scratch[i] = i;
+ shuffle(scratch, state->n, sizeof(int), rs);
+ for (j = 0; j < state->n; j++) {
+ i = scratch[j];
+ if ((state->flags[i] & F_CIRCLE) || (state->flags[i] & F_BLACK)) {
+ debug(("generator skipping (%d,%d): %s", i%w, i/w,
+ (state->flags[i] & F_CIRCLE) ? "CIRCLE" : "BLACK"));
+ continue; /* solver knows this must be one or the other already. */
+ }
+
+ /* Add a random black cell... */
+ solver_op_add(ss, i%w, i/w, BLACK, "Generator: adding random black cell");
+ solver_ops_do(state, ss);
+
+ /* ... and do as well as we know how to lay down whites that are now forced. */
+ solve_allblackbutone(state, ss);
+ solver_ops_do(state, ss);
+
+ solve_removesplits(state, ss);
+ solver_ops_do(state, ss);
+
+ if (state->impossible) {
+ debug(("generator made impossible, restarting..."));
+ goto generate;
+ }
+ }
+ debug_state("State after adding blacks", state);
+
+ /* Now we know which squares are white and which are black, we lay numbers
+ * under black squares at random, except that the number must appear in
+ * white cells at least once more in the same column or row as that [black]
+ * square. That's necessary to avoid multiple solutions, where blackening
+ * squares in the finished puzzle becomes optional. We use two arrays:
+ *
+ * rownums[ROW * o + NUM-1] is the no. of white cells containing NUM in y=ROW
+ * colnums[COL * o + NUM-1] is the no. of white cells containing NUM in x=COL
+ */
+
+ memset(rownums, 0, h*o * sizeof(int));
+ memset(colnums, 0, w*o * sizeof(int));
+ for (i = 0; i < state->n; i++) {
+ if (state->flags[i] & F_BLACK) continue;
+ j = state->nums[i];
+ x = i%w; y = i/w;
+ rownums[y * o + j-1] += 1;
+ colnums[x * o + j-1] += 1;
+ }
+
+ ntries = 0;
+randomise:
+ for (i = 0; i < state->n; i++) {
+ if (!(state->flags[i] & F_BLACK)) continue;
+ state->nums[i] = best_black_col(state, rs, scratch, i, rownums, colnums);
+ }
+ debug_state("State after adding numbers", state);
+
+ /* DIFF_ANY just returns whatever we first generated, for testing purposes. */
+ if (params->diff != DIFF_ANY &&
+ !new_game_is_good(params, state, tosolve)) {
+ ntries++;
+ if (ntries > MAXTRIES) {
+ debug(("Ran out of randomisation attempts, re-generating."));
+ goto generate;
+ }
+ debug(("Re-randomising numbers under black squares."));
+ goto randomise;
+ }
+
+ ret = generate_desc(state, 0);
+
+ free_game(tosolve);
+ free_game(state);
+ solver_state_free(ss);
+ sfree(scratch);
+ sfree(rownums);
+ sfree(colnums);
+
+ return ret;
+}
+
+static char *validate_desc(game_params *params, char *desc)
+{
+ char *ret = NULL;
+
+ unpick_desc(params, desc, NULL, &ret);
+ return ret;
+}
+
+static game_state *new_game(midend *me, game_params *params, char *desc)
+{
+ game_state *state = NULL;
+
+ unpick_desc(params, desc, &state, NULL);
+ if (!state) assert(!"new_game failed to unpick");
+ return state;
+}
+
+/* --- Game UI and move routines --- */
+
+struct game_ui {
+ int cx, cy, cshow;
+ int show_black_nums;
+};
+
+static game_ui *new_ui(game_state *state)
+{
+ game_ui *ui = snew(game_ui);
+
+ ui->cx = ui->cy = ui->cshow = 0;
+ ui->show_black_nums = 0;
+
+ return ui;
+}
+
+static void free_ui(game_ui *ui)
+{
+ sfree(ui);
+}
+
+static char *encode_ui(game_ui *ui)
+{
+ 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)
+{
+ if (!oldstate->completed && newstate->completed)
+ ui->cshow = 0;
+}
+
+#define DS_BLACK 0x1
+#define DS_CIRCLE 0x2
+#define DS_CURSOR 0x4
+#define DS_BLACK_NUM 0x8
+#define DS_ERROR 0x10
+#define DS_FLASH 0x20
+#define DS_IMPOSSIBLE 0x40
+
+struct game_drawstate {
+ int tilesize, started, solved;
+ int w, h, n;
+
+ unsigned int *flags;
+};
+
+static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
+ int mx, int my, int button)
+{
+ char buf[80], c;
+ int i, x = FROMCOORD(mx), y = FROMCOORD(my);
+ enum { NONE, TOGGLE_BLACK, TOGGLE_CIRCLE, UI } action = NONE;
+
+ if (IS_CURSOR_MOVE(button)) {
+ move_cursor(button, &ui->cx, &ui->cy, state->w, state->h, 1);
+ ui->cshow = 1;
+ action = UI;
+ } else if (IS_CURSOR_SELECT(button)) {
+ x = ui->cx; y = ui->cy;
+ if (!ui->cshow) {
+ action = UI;
+ ui->cshow = 1;
+ }
+ if (button == CURSOR_SELECT) {
+ action = TOGGLE_BLACK;
+ } else if (button == CURSOR_SELECT2) {
+ action = TOGGLE_CIRCLE;
+ }
+ } else if (IS_MOUSE_DOWN(button)) {
+ if (ui->cshow) {
+ ui->cshow = 0;
+ action = UI;
+ }
+ if (!INGRID(state, x, y)) {
+ ui->show_black_nums = 1 - ui->show_black_nums;
+ action = UI; /* this wants to be a per-game option. */
+ } else if (button == LEFT_BUTTON) {
+ action = TOGGLE_BLACK;
+ } else if (button == RIGHT_BUTTON) {
+ action = TOGGLE_CIRCLE;
+ }
+ }
+ if (action == UI) return "";
+
+ if (action == TOGGLE_BLACK || action == TOGGLE_CIRCLE) {
+ i = y * state->w + x;
+ if (state->flags[i] & (F_BLACK | F_CIRCLE))
+ c = 'E';
+ else
+ c = (action == TOGGLE_BLACK) ? 'B' : 'C';
+ sprintf(buf, "%c%d,%d", (int)c, x, y);
+ return dupstr(buf);
+ }
+
+ return NULL;
+}
+
+static game_state *execute_move(game_state *state, char *move)
+{
+ game_state *ret = dup_game(state);
+ int x, y, i, n;
+
+ debug(("move: %s", move));
+
+ while (*move) {
+ char c = *move;
+ if (c == 'B' || c == 'C' || c == 'E') {
+ move++;
+ if (sscanf(move, "%d,%d%n", &x, &y, &n) != 2 ||
+ !INGRID(state, x, y))
+ goto badmove;
+
+ i = y*ret->w + x;
+ ret->flags[i] &= ~(F_CIRCLE | F_BLACK); /* empty first, always. */
+ if (c == 'B')
+ ret->flags[i] |= F_BLACK;
+ else if (c == 'C')
+ ret->flags[i] |= F_CIRCLE;
+ move += n;
+ } else if (c == 'S') {
+ move++;
+ ret->used_solve = 1;
+ } else
+ goto badmove;
+
+ if (*move == ';')
+ move++;
+ else if (*move)
+ goto badmove;
+ }
+ if (check_complete(ret, 1)) ret->completed = 1;
+ return ret;
+
+badmove:
+ free_game(ret);
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * Drawing routines.
+ */
+
+static void game_compute_size(game_params *params, int tilesize,
+ int *x, int *y)
+{
+ /* Ick: fake up `ds->tilesize' for macro expansion purposes */
+ struct { int tilesize; } ads, *ds = &ads;
+ ads.tilesize = tilesize;
+
+ *x = TILE_SIZE * params->w + 2 * BORDER;
+ *y = TILE_SIZE * params->h + 2 * BORDER;
+}
+
+static void game_set_size(drawing *dr, game_drawstate *ds,
+ game_params *params, int tilesize)
+{
+ ds->tilesize = tilesize;
+}
+
+static float *game_colours(frontend *fe, int *ncolours)
+{
+ float *ret = snewn(3 * NCOLOURS, float);
+ int i;
+
+ game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT);
+ for (i = 0; i < 3; i++) {
+ ret[COL_BLACK * 3 + i] = 0.0F;
+ ret[COL_BLACKNUM * 3 + i] = 0.4F;
+ ret[COL_WHITE * 3 + i] = 1.0F;
+ ret[COL_GRID * 3 + i] = ret[COL_LOWLIGHT * 3 + i];
+ }
+ ret[COL_CURSOR * 3 + 0] = 0.2F;
+ ret[COL_CURSOR * 3 + 1] = 0.8F;
+ ret[COL_CURSOR * 3 + 2] = 0.0F;
+
+ ret[COL_ERROR * 3 + 0] = 1.0F;
+ ret[COL_ERROR * 3 + 1] = 0.0F;
+ ret[COL_ERROR * 3 + 2] = 0.0F;
+
+ *ncolours = NCOLOURS;
+ return ret;
+}
+
+static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
+{
+ struct game_drawstate *ds = snew(struct game_drawstate);
+
+ ds->tilesize = ds->started = ds->solved = 0;
+ ds->w = state->w;
+ ds->h = state->h;
+ ds->n = state->n;
+
+ ds->flags = snewn(state->n, unsigned int);
+
+ memset(ds->flags, 0, state->n*sizeof(unsigned int));
+
+ return ds;
+}
+
+static void game_free_drawstate(drawing *dr, game_drawstate *ds)
+{
+ sfree(ds->flags);
+ sfree(ds);
+}
+
+static void tile_redraw(drawing *dr, game_drawstate *ds, int x, int y,
+ int num, unsigned int f)
+{
+ int tcol, bg, dnum, cx, cy, tsz;
+ char buf[32];
+
+ if (f & DS_BLACK) {
+ bg = (f & DS_ERROR) ? COL_ERROR : COL_BLACK;
+ tcol = COL_BLACKNUM;
+ dnum = (f & DS_BLACK_NUM) ? 1 : 0;
+ } else {
+ bg = (f & DS_FLASH) ? COL_LOWLIGHT : COL_BACKGROUND;
+ tcol = (f & DS_ERROR) ? COL_ERROR : COL_BLACK;
+ dnum = 1;
+ }
+
+ cx = x + TILE_SIZE/2; cy = y + TILE_SIZE/2;
+
+ draw_rect(dr, x, y, TILE_SIZE, TILE_SIZE, bg);
+ draw_rect_outline(dr, x, y, TILE_SIZE, TILE_SIZE,
+ (f & DS_IMPOSSIBLE) ? COL_ERROR : COL_GRID);
+
+ if (f & DS_CIRCLE) {
+ draw_circle(dr, cx, cy, CRAD, tcol, tcol);
+ draw_circle(dr, cx, cy, CRAD-1, bg, tcol);
+ }
+
+ if (dnum) {
+ sprintf(buf, "%d", num);
+ if (strlen(buf) == 1)
+ tsz = TEXTSZ;
+ else
+ tsz = (CRAD*2 - 1) / strlen(buf);
+ draw_text(dr, cx, cy, FONT_VARIABLE, tsz,
+ ALIGN_VCENTRE | ALIGN_HCENTRE, tcol, buf);
+ }
+
+ if (f & DS_CURSOR)
+ draw_rect_corners(dr, cx, cy, TEXTSZ/2, COL_CURSOR);
+
+ draw_update(dr, x, y, TILE_SIZE, TILE_SIZE);
+}
+
+static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
+ game_state *state, int dir, game_ui *ui,
+ float animtime, float flashtime)
+{
+ int x, y, i, flash;
+ unsigned int f;
+
+ flash = (int)(flashtime * 5 / FLASH_TIME) % 2;
+
+ if (!ds->started) {
+ int wsz = TILE_SIZE * state->w + 2 * BORDER;
+ int hsz = TILE_SIZE * state->h + 2 * BORDER;
+ draw_rect(dr, 0, 0, wsz, hsz, COL_BACKGROUND);
+ draw_rect_outline(dr, COORD(0)-1, COORD(0)-1,
+ TILE_SIZE * state->w + 2, TILE_SIZE * state->h + 2,
+ COL_GRID);
+ draw_update(dr, 0, 0, wsz, hsz);
+ }
+ for (x = 0; x < state->w; x++) {
+ for (y = 0; y < state->h; y++) {
+ i = y*state->w + x;
+ f = 0;
+
+ if (flash) f |= DS_FLASH;
+ if (state->impossible) f |= DS_IMPOSSIBLE;
+
+ if (ui->cshow && x == ui->cx && y == ui->cy)
+ f |= DS_CURSOR;
+ if (state->flags[i] & F_BLACK) {
+ f |= DS_BLACK;
+ if (ui->show_black_nums) f |= DS_BLACK_NUM;
+ }
+ if (state->flags[i] & F_CIRCLE)
+ f |= DS_CIRCLE;
+ if (state->flags[i] & F_ERROR)
+ f |= DS_ERROR;
+
+ if (!ds->started || ds->flags[i] != f) {
+ tile_redraw(dr, ds, COORD(x), COORD(y),
+ state->nums[i], f);
+ ds->flags[i] = f;
+ }
+ }
+ }
+ ds->started = 1;
+}
+
+static float game_anim_length(game_state *oldstate, game_state *newstate,
+ int dir, game_ui *ui)
+{
+ return 0.0F;
+}
+
+static float game_flash_length(game_state *oldstate, game_state *newstate,
+ int dir, game_ui *ui)
+{
+ if (!oldstate->completed &&
+ newstate->completed && !newstate->used_solve)
+ return FLASH_TIME;
+ return 0.0F;
+}
+
+static int game_timing_state(game_state *state, game_ui *ui)
+{
+ return TRUE;
+}
+
+static void game_print_size(game_params *params, float *x, float *y)
+{
+ int pw, ph;
+
+ /* 8mm squares by default. */
+ game_compute_size(params, 800, &pw, &ph);
+ *x = pw / 100.0F;
+ *y = ph / 100.0F;
+}
+
+static void game_print(drawing *dr, game_state *state, int tilesize)
+{
+ int ink = print_mono_colour(dr, 0);
+ int paper = print_mono_colour(dr, 1);
+ int x, y, ox, oy, i;
+ char buf[32];
+
+ /* Ick: fake up `ds->tilesize' for macro expansion purposes */
+ game_drawstate ads, *ds = &ads;
+ game_set_size(dr, ds, NULL, tilesize);
+
+ print_line_width(dr, 2 * TILE_SIZE / 40);
+
+ for (x = 0; x < state->w; x++) {
+ for (y = 0; y < state->h; y++) {
+ ox = COORD(x); oy = COORD(y);
+ i = y*state->w+x;
+
+ if (state->flags[i] & F_BLACK) {
+ draw_rect(dr, ox, oy, TILE_SIZE, TILE_SIZE, ink);
+ } else {
+ draw_rect_outline(dr, ox, oy, TILE_SIZE, TILE_SIZE, ink);
+
+ if (state->flags[i] & DS_CIRCLE)
+ draw_circle(dr, ox+TILE_SIZE/2, oy+TILE_SIZE/2, CRAD,
+ paper, ink);
+
+ sprintf(buf, "%d", state->nums[i]);
+ draw_text(dr, ox+TILE_SIZE/2, oy+TILE_SIZE/2, FONT_VARIABLE,
+ TEXTSZ/strlen(buf), ALIGN_VCENTRE | ALIGN_HCENTRE,
+ ink, buf);
+ }
+ }
+ }
+}
+
+#ifdef COMBINED
+#define thegame singles
+#endif
+
+const struct game thegame = {
+ "Singles", "games.singles", "singles",
+ default_params,
+ game_fetch_preset,
+ decode_params,
+ encode_params,
+ free_params,
+ dup_params,
+ TRUE, game_configure, custom_params,
+ validate_params,
+ new_game_desc,
+ validate_desc,
+ new_game,
+ dup_game,
+ free_game,
+ TRUE, solve_game,
+ TRUE, game_can_format_as_text_now, game_text_format,
+ new_ui,
+ free_ui,
+ 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,
+ game_redraw,
+ game_anim_length,
+ game_flash_length,
+ TRUE, FALSE, game_print_size, game_print,
+ FALSE, /* wants_statusbar */
+ FALSE, game_timing_state,
+ REQUIRE_RBUTTON, /* flags */
+};
+
+#ifdef STANDALONE_SOLVER
+
+#include <time.h>
+#include <stdarg.h>
+
+static void start_soak(game_params *p, random_state *rs)
+{
+ time_t tt_start, tt_now, tt_last;
+ char *desc, *aux;
+ game_state *s;
+ int i, n = 0, ndiff[DIFF_MAX], diff, sret, nblack = 0, nsneaky = 0;
+
+ tt_start = tt_now = time(NULL);
+
+ printf("Soak-testing a %dx%d grid.\n", p->w, p->h);
+ p->diff = DIFF_ANY;
+
+ memset(ndiff, 0, DIFF_MAX * sizeof(int));
+
+ while (1) {
+ n++;
+ desc = new_game_desc(p, rs, &aux, 0);
+ s = new_game(NULL, p, desc);
+ nsneaky += solve_sneaky(s, NULL);
+
+ for (diff = 0; diff < DIFF_MAX; diff++) {
+ memset(s->flags, 0, s->n * sizeof(unsigned int));
+ s->completed = s->impossible = 0;
+ sret = solve_specific(s, diff, 0);
+ if (sret > 0) {
+ ndiff[diff]++;
+ break;
+ } else if (sret < 0)
+ fprintf(stderr, "Impossible! %s\n", desc);
+ }
+ for (i = 0; i < s->n; i++) {
+ if (s->flags[i] & F_BLACK) nblack++;
+ }
+ free_game(s);
+ sfree(desc);
+
+ tt_last = time(NULL);
+ if (tt_last > tt_now) {
+ tt_now = tt_last;
+ printf("%d total, %3.1f/s, bl/sn %3.1f%%/%3.1f%%: ",
+ n, (double)n / ((double)tt_now - tt_start),
+ ((double)nblack * 100.0) / (double)(n * p->w * p->h),
+ ((double)nsneaky * 100.0) / (double)(n * p->w * p->h));
+ for (diff = 0; diff < DIFF_MAX; diff++) {
+ if (diff > 0) printf(", ");
+ printf("%d (%3.1f%%) %s",
+ ndiff[diff], (double)ndiff[diff] * 100.0 / (double)n,
+ singles_diffnames[diff]);
+ }
+ printf("\n");
+ }
+ }
+}
+
+int main(int argc, char **argv)
+{
+ char *id = NULL, *desc, *desc_gen = NULL, *tgame, *err, *aux;
+ game_state *s = NULL;
+ game_params *p = NULL;
+ int soln, soak = 0, ret = 1;
+ time_t seed = time(NULL);
+ random_state *rs = NULL;
+
+ setvbuf(stdout, NULL, _IONBF, 0);
+
+ while (--argc > 0) {
+ char *p = *++argv;
+ if (!strcmp(p, "-v")) {
+ verbose = 1;
+ } else if (!strcmp(p, "--soak")) {
+ soak = 1;
+ } else if (!strcmp(p, "--seed")) {
+ if (argc == 0) {
+ fprintf(stderr, "%s: --seed needs an argument", argv[0]);
+ goto done;
+ }
+ seed = (time_t)atoi(*++argv);
+ argc--;
+ } else if (*p == '-') {
+ fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
+ return 1;
+ } else {
+ id = p;
+ }
+ }
+
+ rs = random_new((void*)&seed, sizeof(time_t));
+
+ if (!id) {
+ fprintf(stderr, "usage: %s [-v] [--soak] <params> | <game_id>\n", argv[0]);
+ goto done;
+ }
+ desc = strchr(id, ':');
+ if (desc) *desc++ = '\0';
+
+ p = default_params();
+ decode_params(p, id);
+ err = validate_params(p, 1);
+ if (err) {
+ fprintf(stderr, "%s: %s", argv[0], err);
+ goto done;
+ }
+
+ if (soak) {
+ if (desc) {
+ fprintf(stderr, "%s: --soak only needs params, not game desc.\n", argv[0]);
+ goto done;
+ }
+ start_soak(p, rs);
+ } else {
+ if (!desc) desc = desc_gen = new_game_desc(p, rs, &aux, 0);
+
+ err = validate_desc(p, desc);
+ if (err) {
+ fprintf(stderr, "%s: %s\n", argv[0], err);
+ free_params(p);
+ goto done;
+ }
+ s = new_game(NULL, p, desc);
+
+ if (verbose) {
+ tgame = game_text_format(s);
+ printf(tgame);
+ sfree(tgame);
+ }
+
+ soln = solve_specific(s, DIFF_ANY, 0);
+ tgame = game_text_format(s);
+ printf(tgame);
+ sfree(tgame);
+ printf("Game was %s.\n\n",
+ soln < 0 ? "impossible" : soln > 0 ? "solved" : "not solved");
+ }
+ ret = 0;
+
+done:
+ if (desc_gen) sfree(desc_gen);
+ if (p) free_params(p);
+ if (s) free_game(s);
+ if (rs) random_free(rs);
+
+ return ret;
+}
+
+#endif
+
+
+/* vim: set shiftwidth=4 tabstop=8: */
~mdw / sgt / puzzles / commitdiff