#include "puzzles.h"
/*
+ * In standalone solver mode, `verbose' is a variable which can be
+ * set by command-line option; in debugging mode it's simply always
+ * true.
+ */
+#if defined STANDALONE_SOLVER
+#define SOLVER_DIAGNOSTICS
+int verbose = FALSE;
+#elif defined SOLVER_DIAGNOSTICS
+#define verbose TRUE
+#endif
+
+/*
* I don't seriously anticipate wanting to change the number of
* colours used in this game, but it doesn't cost much to use a
* #define just in case :-)
int n;
int ngraph;
int *immutable;
- int *edgex, *edgey; /* positions of a point on each edge */
+ int *edgex, *edgey; /* position of a point on each edge */
+ int *regionx, *regiony; /* position of a point in each region */
};
struct game_state {
struct solver_scratch {
unsigned char *possible; /* bitmap of colours for each region */
+
int *graph;
- int *bfsqueue;
- int *bfscolour;
int n;
int ngraph;
+
+ int *bfsqueue;
+ int *bfscolour;
+#ifdef SOLVER_DIAGNOSTICS
+ int *bfsprev;
+#endif
+
int depth;
};
sc->depth = 0;
sc->bfsqueue = snewn(n, int);
sc->bfscolour = snewn(n, int);
+#ifdef SOLVER_DIAGNOSTICS
+ sc->bfsprev = snewn(n, int);
+#endif
return sc;
}
sfree(sc->possible);
sfree(sc->bfsqueue);
sfree(sc->bfscolour);
+#ifdef SOLVER_DIAGNOSTICS
+ sfree(sc->bfsprev);
+#endif
sfree(sc);
}
return word;
}
+#ifdef SOLVER_DIAGNOSTICS
+static const char colnames[FOUR] = { 'R', 'Y', 'G', 'B' };
+#endif
+
static int place_colour(struct solver_scratch *sc,
- int *colouring, int index, int colour)
+ int *colouring, int index, int colour
+#ifdef SOLVER_DIAGNOSTICS
+ , char *verb
+#endif
+ )
{
int *graph = sc->graph, n = sc->n, ngraph = sc->ngraph;
int j, k;
- if (!(sc->possible[index] & (1 << colour)))
+ if (!(sc->possible[index] & (1 << colour))) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*scannot place %c in region %d\n", 2*sc->depth, "",
+ colnames[colour], index);
+#endif
return FALSE; /* can't do it */
+ }
sc->possible[index] = 1 << colour;
colouring[index] = colour;
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*s%s %c in region %d\n", 2*sc->depth, "",
+ verb, colnames[colour], index);
+#endif
+
/*
* Rule out this colour from all the region's neighbours.
*/
for (j = graph_vertex_start(graph, n, ngraph, index);
j < ngraph && graph[j] < n*(index+1); j++) {
k = graph[j] - index*n;
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose && (sc->possible[k] & (1 << colour)))
+ printf("%*s ruling out %c in region %d\n", 2*sc->depth, "",
+ colnames[colour], k);
+#endif
sc->possible[k] &= ~(1 << colour);
}
return TRUE;
}
+#ifdef SOLVER_DIAGNOSTICS
+static char *colourset(char *buf, int set)
+{
+ int i;
+ char *p = buf;
+ char *sep = "";
+
+ for (i = 0; i < FOUR; i++)
+ if (set & (1 << i)) {
+ p += sprintf(p, "%s%c", sep, colnames[i]);
+ sep = ",";
+ }
+
+ return buf;
+}
+#endif
+
/*
* Returns 0 for impossible, 1 for success, 2 for failure to
* converge (i.e. puzzle is either ambiguous or just too
{
int i;
- /*
- * Initialise scratch space.
- */
- for (i = 0; i < n; i++)
- sc->possible[i] = (1 << FOUR) - 1;
+ if (sc->depth == 0) {
+ /*
+ * Initialise scratch space.
+ */
+ for (i = 0; i < n; i++)
+ sc->possible[i] = (1 << FOUR) - 1;
- /*
- * Place clues.
- */
- for (i = 0; i < n; i++)
- if (colouring[i] >= 0) {
- if (!place_colour(sc, colouring, i, colouring[i]))
- return 0; /* the clues aren't even consistent! */
- }
+ /*
+ * Place clues.
+ */
+ for (i = 0; i < n; i++)
+ if (colouring[i] >= 0) {
+ if (!place_colour(sc, colouring, i, colouring[i]
+#ifdef SOLVER_DIAGNOSTICS
+ , "initial clue:"
+#endif
+ )) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*sinitial clue set is inconsistent\n",
+ 2*sc->depth, "");
+#endif
+ return 0; /* the clues aren't even consistent! */
+ }
+ }
+ }
/*
* Now repeatedly loop until we find nothing further to do.
for (i = 0; i < n; i++) if (colouring[i] < 0) {
int p = sc->possible[i];
- if (p == 0)
+ if (p == 0) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*sregion %d has no possible colours left\n",
+ 2*sc->depth, "", i);
+#endif
return 0; /* puzzle is inconsistent */
+ }
if ((p & (p-1)) == 0) { /* p is a power of two */
- int c;
+ int c, ret;
for (c = 0; c < FOUR; c++)
if (p == (1 << c))
break;
assert(c < FOUR);
- if (!place_colour(sc, colouring, i, c))
- return 0; /* found puzzle to be inconsistent */
+ ret = place_colour(sc, colouring, i, c
+#ifdef SOLVER_DIAGNOSTICS
+ , "placing"
+#endif
+ );
+ /*
+ * place_colour() can only fail if colour c was not
+ * even a _possibility_ for region i, and we're
+ * pretty sure it was because we checked before
+ * calling place_colour(). So we can safely assert
+ * here rather than having to return a nice
+ * friendly error code.
+ */
+ assert(ret);
done_something = TRUE;
}
}
for (i = 0; i < ngraph; i++) {
int j1 = graph[i] / n, j2 = graph[i] % n;
int j, k, v, v2;
+#ifdef SOLVER_DIAGNOSTICS
+ int started = FALSE;
+#endif
if (j1 > j2)
continue; /* done it already, other way round */
k = graph[j] - j1*n;
if (graph_adjacent(graph, n, ngraph, k, j2) &&
(sc->possible[k] & v)) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose) {
+ char buf[80];
+ if (!started)
+ printf("%*sadjacent regions %d,%d share colours"
+ " %s\n", 2*sc->depth, "", j1, j2,
+ colourset(buf, v));
+ started = TRUE;
+ printf("%*s ruling out %s in region %d\n",2*sc->depth,
+ "", colourset(buf, sc->possible[k] & v), k);
+ }
+#endif
sc->possible[k] &= ~v;
done_something = TRUE;
}
origc = 1 << c;
- for (j = 0; j < n; j++)
+ for (j = 0; j < n; j++) {
sc->bfscolour[j] = -1;
+#ifdef SOLVER_DIAGNOSTICS
+ sc->bfsprev[j] = -1;
+#endif
+ }
head = tail = 0;
sc->bfsqueue[tail++] = i;
sc->bfscolour[i] = sc->possible[i] &~ origc;
sc->bfsqueue[tail++] = k;
sc->bfscolour[k] =
sc->possible[k] &~ currc;
+#ifdef SOLVER_DIAGNOSTICS
+ sc->bfsprev[k] = j;
+#endif
}
/*
if (currc == origc &&
graph_adjacent(graph, n, ngraph, k, i) &&
(sc->possible[k] & currc)) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose) {
+ char buf[80], *sep = "";
+ int r;
+
+ printf("%*sforcing chain, colour %s, ",
+ 2*sc->depth, "",
+ colourset(buf, origc));
+ for (r = j; r != -1; r = sc->bfsprev[r]) {
+ printf("%s%d", sep, r);
+ sep = "-";
+ }
+ printf("\n%*s ruling out %s in region"
+ " %d\n", 2*sc->depth, "",
+ colourset(buf, origc), k);
+ }
+#endif
sc->possible[k] &= ~origc;
done_something = TRUE;
}
for (i = 0; i < n; i++)
if (colouring[i] < 0)
break;
- if (i == n)
+ if (i == n) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*sone solution found\n", 2*sc->depth, "");
+#endif
return 1; /* success! */
+ }
/*
* If recursion is not permissible, we now give up.
*/
- if (difficulty < DIFF_RECURSE)
+ if (difficulty < DIFF_RECURSE) {
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*sunable to proceed further without recursion\n",
+ 2*sc->depth, "");
+#endif
return 2; /* unable to complete */
+ }
/*
* Now we've got to do something recursive. So first hunt for a
assert(best >= 0); /* or we'd be solved already */
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose)
+ printf("%*srecursing on region %d\n", 2*sc->depth, "", best);
+#endif
+
/*
* Now iterate over the possible colours for this region.
*/
if (!(sc->possible[best] & (1 << i)))
continue;
+ memcpy(rsc->possible, sc->possible, n);
memcpy(subcolouring, origcolouring, n * sizeof(int));
- subcolouring[best] = i;
+
+ place_colour(rsc, subcolouring, best, i
+#ifdef SOLVER_DIAGNOSTICS
+ , "trying"
+#endif
+ );
+
subret = map_solver(rsc, graph, n, ngraph,
subcolouring, difficulty);
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose) {
+ printf("%*sretracting %c in region %d; found %s\n",
+ 2*sc->depth, "", colnames[i], best,
+ subret == 0 ? "no solutions" :
+ subret == 1 ? "one solution" : "multiple solutions");
+ }
+#endif
+
/*
* If this possibility turned up more than one valid
* solution, or if it turned up one and we already had
sfree(subcolouring);
free_scratch(rsc);
+#ifdef SOLVER_DIAGNOSTICS
+ if (verbose && sc->depth == 0) {
+ printf("%*s%s found\n",
+ 2*sc->depth, "",
+ ret == 0 ? "no solutions" :
+ ret == 1 ? "one solution" : "multiple solutions");
+ }
+#endif
return ret;
}
}
/*
* Analyse the map to find a canonical line segment
- * corresponding to each edge. These are where we'll eventually
- * put error markers.
+ * corresponding to each edge, and a canonical point
+ * corresponding to each region. The former are where we'll
+ * eventually put error markers; the latter are where we'll put
+ * per-region flags such as numbers (when in diagnostic mode).
*/
{
int *bestx, *besty, *an, pass;
float *ax, *ay, *best;
- ax = snewn(state->map->ngraph, float);
- ay = snewn(state->map->ngraph, float);
- an = snewn(state->map->ngraph, int);
- bestx = snewn(state->map->ngraph, int);
- besty = snewn(state->map->ngraph, int);
- best = snewn(state->map->ngraph, float);
+ ax = snewn(state->map->ngraph + n, float);
+ ay = snewn(state->map->ngraph + n, float);
+ an = snewn(state->map->ngraph + n, int);
+ bestx = snewn(state->map->ngraph + n, int);
+ besty = snewn(state->map->ngraph + n, int);
+ best = snewn(state->map->ngraph + n, float);
- for (i = 0; i < state->map->ngraph; i++) {
+ for (i = 0; i < state->map->ngraph + n; i++) {
bestx[i] = besty[i] = -1;
best[i] = 2*(w+h)+1;
ax[i] = ay[i] = 0.0F;
/*
* We make two passes over the map, finding all the line
- * segments separating regions. In the first pass, we
- * compute the _average_ x and y coordinate of all the line
- * segments separating each pair of regions; in the second
- * pass, for each such average point, we find the line
- * segment closest to it and call that canonical.
+ * segments separating regions and all the suitable points
+ * within regions. In the first pass, we compute the
+ * _average_ x and y coordinate of all the points in a
+ * given class; in the second pass, for each such average
+ * point, we find the candidate closest to it and call that
+ * canonical.
*
* Line segments are considered to have coordinates in
* their centre. Thus, at least one coordinate for any line
/* right edge */
ea[en] = state->map->map[RE * wh + y*w+x];
eb[en] = state->map->map[LE * wh + y*w+(x+1)];
- if (ea[en] != eb[en]) {
- ex[en] = (x+1)*2;
- ey[en] = y*2+1;
- en++;
- }
+ ex[en] = (x+1)*2;
+ ey[en] = y*2+1;
+ en++;
}
if (y+1 < h) {
/* bottom edge */
ea[en] = state->map->map[BE * wh + y*w+x];
eb[en] = state->map->map[TE * wh + (y+1)*w+x];
- if (ea[en] != eb[en]) {
- ex[en] = x*2+1;
- ey[en] = (y+1)*2;
- en++;
- }
+ ex[en] = x*2+1;
+ ey[en] = (y+1)*2;
+ en++;
}
/* diagonal edge */
ea[en] = state->map->map[TE * wh + y*w+x];
eb[en] = state->map->map[BE * wh + y*w+x];
- if (ea[en] != eb[en]) {
- ex[en] = x*2+1;
- ey[en] = y*2+1;
- en++;
- }
+ ex[en] = x*2+1;
+ ey[en] = y*2+1;
+ en++;
+
if (x+1 < w && y+1 < h) {
/* bottom right corner */
int oct[8], othercol, nchanges;
ey[en] = (y+1)*2;
en++;
}
+
+ /*
+ * If there's exactly _one_ region at this
+ * point, on the other hand, it's a valid
+ * place to put a region centre.
+ */
+ if (othercol < 0) {
+ ea[en] = eb[en] = oct[0];
+ ex[en] = (x+1)*2;
+ ey[en] = (y+1)*2;
+ en++;
+ }
}
/*
- * Now process the edges we've found, one by
+ * Now process the points we've found, one by
* one.
*/
for (i = 0; i < en; i++) {
int emin = min(ea[i], eb[i]);
int emax = max(ea[i], eb[i]);
- int gindex =
- graph_edge_index(state->map->graph, n,
- state->map->ngraph, emin, emax);
+ int gindex;
+
+ if (emin != emax) {
+ /* Graph edge */
+ gindex =
+ graph_edge_index(state->map->graph, n,
+ state->map->ngraph, emin,
+ emax);
+ } else {
+ /* Region number */
+ gindex = state->map->ngraph + emin;
+ }
assert(gindex >= 0);
}
if (pass == 0) {
- for (i = 0; i < state->map->ngraph; i++)
+ for (i = 0; i < state->map->ngraph + n; i++)
if (an[i] > 0) {
ax[i] /= an[i];
ay[i] /= an[i];
}
}
- state->map->edgex = bestx;
- state->map->edgey = besty;
+ state->map->edgex = snewn(state->map->ngraph, int);
+ state->map->edgey = snewn(state->map->ngraph, int);
+ memcpy(state->map->edgex, bestx, state->map->ngraph * sizeof(int));
+ memcpy(state->map->edgey, besty, state->map->ngraph * sizeof(int));
+
+ state->map->regionx = snewn(n, int);
+ state->map->regiony = snewn(n, int);
+ memcpy(state->map->regionx, bestx + state->map->ngraph, n*sizeof(int));
+ memcpy(state->map->regiony, besty + state->map->ngraph, n*sizeof(int));
for (i = 0; i < state->map->ngraph; i++)
if (state->map->edgex[i] < 0) {
sfree(ay);
sfree(an);
sfree(best);
+ sfree(bestx);
+ sfree(besty);
}
return state;
sfree(state->map->immutable);
sfree(state->map->edgex);
sfree(state->map->edgey);
+ sfree(state->map->regionx);
+ sfree(state->map->regiony);
sfree(state->map);
}
sfree(state->colouring);
struct game_ui {
int drag_colour; /* -1 means no drag active */
int dragx, dragy;
+ int show_numbers;
};
static game_ui *new_ui(game_state *state)
game_ui *ui = snew(game_ui);
ui->dragx = ui->dragy = -1;
ui->drag_colour = -2;
+ ui->show_numbers = FALSE;
return ui;
}
};
/* Flags in `drawn'. */
-#define ERR_BASE 0x00800000L
-#define ERR_MASK 0xFF800000L
+#define ERR_BASE 0x00800000L
+#define ERR_MASK 0xFF800000L
#define PENCIL_T_BASE 0x00080000L
#define PENCIL_T_MASK 0x00780000L
#define PENCIL_B_BASE 0x00008000L
#define PENCIL_B_MASK 0x00078000L
#define PENCIL_MASK 0x007F8000L
+#define SHOW_NUMBERS 0x00004000L
#define TILESIZE (ds->tilesize)
#define BORDER (TILESIZE)
{
char buf[80];
+ /*
+ * Enable or disable numeric labels on regions.
+ */
+ if (button == 'l' || button == 'L') {
+ ui->show_numbers = !ui->show_numbers;
+ return "";
+ }
+
if (button == LEFT_BUTTON || button == RIGHT_BUTTON) {
int r = region_from_coords(state, ds, x, y);
int x, int y, int v)
{
int w = params->w, h = params->h, wh = w*h;
- int tv, bv, xo, yo, errs, pencil;
+ int tv, bv, xo, yo, errs, pencil, i, j, oldj;
+ int show_numbers;
errs = v & ERR_MASK;
v &= ~ERR_MASK;
pencil = v & PENCIL_MASK;
v &= ~PENCIL_MASK;
+ show_numbers = v & SHOW_NUMBERS;
+ v &= ~SHOW_NUMBERS;
tv = v / FIVE;
bv = v % FIVE;
(COORD(x)*2+TILESIZE*xo)/2,
(COORD(y)*2+TILESIZE*yo)/2);
+ /*
+ * Draw region numbers, if desired.
+ */
+ if (show_numbers) {
+ oldj = -1;
+ for (i = 0; i < 2; i++) {
+ j = map->map[(i?BE:TE)*wh+y*w+x];
+ if (oldj == j)
+ continue;
+ oldj = j;
+
+ xo = map->regionx[j] - 2*x;
+ yo = map->regiony[j] - 2*y;
+ if (xo >= 0 && xo <= 2 && yo >= 0 && yo <= 2) {
+ char buf[80];
+ sprintf(buf, "%d", j);
+ draw_text(dr, (COORD(x)*2+TILESIZE*xo)/2,
+ (COORD(y)*2+TILESIZE*yo)/2,
+ FONT_VARIABLE, 3*TILESIZE/5,
+ ALIGN_HCENTRE|ALIGN_VCENTRE,
+ COL_GRID, buf);
+ }
+ }
+ }
+
unclip(dr);
draw_update(dr, COORD(x), COORD(y), TILESIZE, TILESIZE);
v |= PENCIL_B_BASE << i;
}
+ if (ui->show_numbers)
+ v |= SHOW_NUMBERS;
+
ds->todraw[y*w+x] = v;
}
else
d2 = i;
}
-/* printf("%% %d,%d r=%d: d1=%d d2=%d lastdir=%d\n", x, y, r, d1, d2, lastdir); */
+
assert(d1 != -1 && d2 != -1);
if (d1 == lastdir)
d1 = d2;
FALSE, game_timing_state,
0, /* mouse_priorities */
};
+
+#ifdef STANDALONE_SOLVER
+
+#include <stdarg.h>
+
+void frontend_default_colour(frontend *fe, float *output) {}
+void draw_text(drawing *dr, int x, int y, int fonttype, int fontsize,
+ int align, int colour, char *text) {}
+void draw_rect(drawing *dr, int x, int y, int w, int h, int colour) {}
+void draw_line(drawing *dr, int x1, int y1, int x2, int y2, int colour) {}
+void draw_polygon(drawing *dr, int *coords, int npoints,
+ int fillcolour, int outlinecolour) {}
+void draw_circle(drawing *dr, int cx, int cy, int radius,
+ int fillcolour, int outlinecolour) {}
+void clip(drawing *dr, int x, int y, int w, int h) {}
+void unclip(drawing *dr) {}
+void start_draw(drawing *dr) {}
+void draw_update(drawing *dr, int x, int y, int w, int h) {}
+void end_draw(drawing *dr) {}
+blitter *blitter_new(drawing *dr, int w, int h) {return NULL;}
+void blitter_free(drawing *dr, blitter *bl) {}
+void blitter_save(drawing *dr, blitter *bl, int x, int y) {}
+void blitter_load(drawing *dr, blitter *bl, int x, int y) {}
+int print_mono_colour(drawing *dr, int grey) { return 0; }
+int print_rgb_colour(drawing *dr, int hatch, float r, float g, float b)
+{ return 0; }
+void print_line_width(drawing *dr, int width) {}
+
+void fatal(char *fmt, ...)
+{
+ va_list ap;
+
+ fprintf(stderr, "fatal error: ");
+
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+
+ fprintf(stderr, "\n");
+ exit(1);
+}
+
+int main(int argc, char **argv)
+{
+ game_params *p;
+ game_state *s;
+ char *id = NULL, *desc, *err;
+ int grade = FALSE;
+ int ret, diff, really_verbose = FALSE;
+ struct solver_scratch *sc;
+ int i;
+
+ while (--argc > 0) {
+ char *p = *++argv;
+ if (!strcmp(p, "-v")) {
+ really_verbose = TRUE;
+ } else if (!strcmp(p, "-g")) {
+ grade = TRUE;
+ } else if (*p == '-') {
+ fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
+ return 1;
+ } else {
+ id = p;
+ }
+ }
+
+ if (!id) {
+ fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]);
+ return 1;
+ }
+
+ desc = strchr(id, ':');
+ if (!desc) {
+ fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]);
+ return 1;
+ }
+ *desc++ = '\0';
+
+ 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(NULL, p, desc);
+
+ sc = new_scratch(s->map->graph, s->map->n, s->map->ngraph);
+
+ /*
+ * When solving an Easy puzzle, we don't want to bother the
+ * user with Hard-level deductions. For this reason, we grade
+ * the puzzle internally before doing anything else.
+ */
+ ret = -1; /* placate optimiser */
+ for (diff = 0; diff < DIFFCOUNT; diff++) {
+ for (i = 0; i < s->map->n; i++)
+ if (!s->map->immutable[i])
+ s->colouring[i] = -1;
+ ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph,
+ s->colouring, diff);
+ if (ret < 2)
+ break;
+ }
+
+ if (diff == DIFFCOUNT) {
+ if (grade)
+ printf("Difficulty rating: harder than Hard, or ambiguous\n");
+ else
+ printf("Unable to find a unique solution\n");
+ } else {
+ if (grade) {
+ if (ret == 0)
+ printf("Difficulty rating: impossible (no solution exists)\n");
+ else if (ret == 1)
+ printf("Difficulty rating: %s\n", map_diffnames[diff]);
+ } else {
+ verbose = really_verbose;
+ for (i = 0; i < s->map->n; i++)
+ if (!s->map->immutable[i])
+ s->colouring[i] = -1;
+ ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph,
+ s->colouring, diff);
+ if (ret == 0)
+ printf("Puzzle is inconsistent\n");
+ else {
+ int col = 0;
+
+ for (i = 0; i < s->map->n; i++) {
+ printf("%5d <- %c%c", i, colnames[s->colouring[i]],
+ (col < 6 && i+1 < s->map->n ? ' ' : '\n'));
+ if (++col == 7)
+ col = 0;
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+#endif
~mdw / sgt / puzzles / blobdiff