*
* TODO:
*
+ * - Jigsaw Sudoku is currently an undocumented feature enabled
+ * by setting r (`Rows of sub-blocks' in the GUI configurer) to
+ * 1. The reason it's undocumented is because they're rather
+ * erratic to generate, because gridgen tends to hang up for
+ * ages. I think this is because some jigsaw block layouts
+ * simply do not admit very many valid filled grids (and
+ * perhaps some have none at all).
+ * + To fix this, I think probably the solution is a change in
+ * grid generation policy: gridgen needs to have less of an
+ * all-or-nothing attitude and instead make only a limited
+ * amount of effort to construct a filled grid before giving
+ * up and trying a new layout. (Come to think of it, this
+ * same change might also make 5x5 standard Sudoku more
+ * practical to generate, if correctly tuned.)
+ * + If I get this fixed, other work needed on jigsaw mode is:
+ * * introduce a GUI config checkbox. game_configure()
+ * ticks this box iff r==1; if it's ticked in a call to
+ * custom_params(), we replace (c, r) with (c*r, 1).
+ * * document it.
+ *
* - 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
#define PREFERRED_TILE_SIZE 32
#define TILE_SIZE (ds->tilesize)
#define BORDER (TILE_SIZE / 2)
+#define GRIDEXTRA (TILE_SIZE / 32)
#define FLASH_TIME 0.4F
enum {
COL_BACKGROUND,
+ COL_XDIAGONALS,
COL_GRID,
COL_CLUE,
COL_USER,
};
struct game_params {
+ /*
+ * For a square puzzle, `c' and `r' indicate the puzzle
+ * parameters as described above.
+ *
+ * A jigsaw-style puzzle is indicated by r==1, in which case c
+ * can be whatever it likes (there is no constraint on
+ * compositeness - a 7x7 jigsaw sudoku makes perfect sense).
+ */
int c, r, symm, diff;
+ int xtype; /* require all digits in X-diagonals */
};
-struct game_state {
+struct block_structure {
+ int refcount;
+
+ /*
+ * For text formatting, we do need c and r here.
+ */
int c, r;
+
+ /*
+ * For any square index, whichblock[i] gives its block index.
+ *
+ * For 0 <= b,i < cr, blocks[b][i] gives the index of the ith
+ * square in block b.
+ *
+ * whichblock and blocks are each dynamically allocated in
+ * their own right, but the subarrays in blocks are appended
+ * to the whichblock array, so shouldn't be freed
+ * individually.
+ */
+ int *whichblock, **blocks;
+
+#ifdef STANDALONE_SOLVER
+ /*
+ * Textual descriptions of each block. For normal Sudoku these
+ * are of the form "(1,3)"; for jigsaw they are "starting at
+ * (5,7)". So the sensible usage in both cases is to say
+ * "elimination within block %s" with one of these strings.
+ *
+ * Only blocknames itself needs individually freeing; it's all
+ * one block.
+ */
+ char **blocknames;
+#endif
+};
+
+struct game_state {
+ /*
+ * For historical reasons, I use `cr' to denote the overall
+ * width/height of the puzzle. It was a natural notation when
+ * all puzzles were divided into blocks in a grid, but doesn't
+ * really make much sense given jigsaw puzzles. However, the
+ * obvious `n' is heavily used in the solver to describe the
+ * index of a number being placed, so `cr' will have to stay.
+ */
+ int cr;
+ struct block_structure *blocks;
+ int xtype;
digit *grid;
unsigned char *pencil; /* c*r*c*r elements */
unsigned char *immutable; /* marks which digits are clues */
game_params *ret = snew(game_params);
ret->c = ret->r = 3;
+ ret->xtype = FALSE;
ret->symm = SYMM_ROT2; /* a plausible default */
ret->diff = DIFF_BLOCK; /* so is this */
char *title;
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 Extreme", { 3, 3, SYMM_ROT2, DIFF_EXTREME } },
- { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE } },
+ { "2x2 Trivial", { 2, 2, SYMM_ROT2, DIFF_BLOCK, FALSE } },
+ { "2x3 Basic", { 2, 3, SYMM_ROT2, DIFF_SIMPLE, FALSE } },
+ { "3x3 Trivial", { 3, 3, SYMM_ROT2, DIFF_BLOCK, FALSE } },
+ { "3x3 Basic", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, FALSE } },
+ { "3x3 Basic X", { 3, 3, SYMM_ROT2, DIFF_SIMPLE, TRUE } },
+ { "3x3 Intermediate", { 3, 3, SYMM_ROT2, DIFF_INTERSECT, FALSE } },
+ { "3x3 Advanced", { 3, 3, SYMM_ROT2, DIFF_SET, FALSE } },
+ { "3x3 Advanced X", { 3, 3, SYMM_ROT2, DIFF_SET, TRUE } },
+ { "3x3 Extreme", { 3, 3, SYMM_ROT2, DIFF_EXTREME, FALSE } },
+ { "3x3 Unreasonable", { 3, 3, SYMM_ROT2, DIFF_RECURSIVE, FALSE } },
#ifndef SLOW_SYSTEM
- { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE } },
- { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE } },
+ { "3x4 Basic", { 3, 4, SYMM_ROT2, DIFF_SIMPLE, FALSE } },
+ { "4x4 Basic", { 4, 4, SYMM_ROT2, DIFF_SIMPLE, FALSE } },
#endif
};
static void decode_params(game_params *ret, char const *string)
{
+ int seen_r = FALSE;
+
ret->c = ret->r = atoi(string);
+ ret->xtype = FALSE;
while (*string && isdigit((unsigned char)*string)) string++;
if (*string == 'x') {
string++;
ret->r = atoi(string);
+ seen_r = TRUE;
while (*string && isdigit((unsigned char)*string)) string++;
}
while (*string) {
- if (*string == 'r' || *string == 'm' || *string == 'a') {
+ if (*string == 'j') {
+ string++;
+ if (seen_r)
+ ret->c *= ret->r;
+ ret->r = 1;
+ } else if (*string == 'x') {
+ string++;
+ ret->xtype = TRUE;
+ } else if (*string == 'r' || *string == 'm' || *string == 'a') {
int sn, sc, sd;
sc = *string++;
if (sc == 'm' && *string == 'd') {
{
char str[80];
- sprintf(str, "%dx%d", params->c, params->r);
+ if (params->r > 1)
+ sprintf(str, "%dx%d", params->c, params->r);
+ else
+ sprintf(str, "%dj", params->c);
+ if (params->xtype)
+ strcat(str, "x");
+
if (full) {
switch (params->symm) {
case SYMM_REF8: strcat(str, "m8"); break;
config_item *ret;
char buf[80];
- ret = snewn(5, config_item);
+ ret = snewn(6, config_item);
ret[0].name = "Columns of sub-blocks";
ret[0].type = C_STRING;
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
- ret[2].name = "Symmetry";
- ret[2].type = C_CHOICES;
- ret[2].sval = ":None:2-way rotation:4-way rotation:2-way mirror:"
+ ret[2].name = "\"X\" (require every number in each main diagonal)";
+ ret[2].type = C_BOOLEAN;
+ ret[2].sval = NULL;
+ ret[2].ival = params->xtype;
+
+ ret[3].name = "Symmetry";
+ ret[3].type = C_CHOICES;
+ ret[3].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].ival = params->symm;
- ret[3].name = "Difficulty";
- ret[3].type = C_CHOICES;
- ret[3].sval = ":Trivial:Basic:Intermediate:Advanced:Extreme:Unreasonable";
- ret[3].ival = params->diff;
+ ret[4].name = "Difficulty";
+ ret[4].type = C_CHOICES;
+ ret[4].sval = ":Trivial:Basic:Intermediate:Advanced:Extreme:Unreasonable";
+ ret[4].ival = params->diff;
- ret[4].name = NULL;
- ret[4].type = C_END;
- ret[4].sval = NULL;
- ret[4].ival = 0;
+ ret[5].name = NULL;
+ ret[5].type = C_END;
+ ret[5].sval = NULL;
+ ret[5].ival = 0;
return ret;
}
ret->c = atoi(cfg[0].sval);
ret->r = atoi(cfg[1].sval);
- ret->symm = cfg[2].ival;
- ret->diff = cfg[3].ival;
+ ret->xtype = cfg[2].ival;
+ ret->symm = cfg[3].ival;
+ ret->diff = cfg[4].ival;
return ret;
}
static char *validate_params(game_params *params, int full)
{
- if (params->c < 2 || params->r < 2)
+ if (params->c < 2)
return "Both dimensions must be at least 2";
if (params->c > ORDER_MAX || params->r > ORDER_MAX)
return "Dimensions greater than "STR(ORDER_MAX)" are not supported";
* the numbers' possible positions (or the spaces' possible
* contents).
*
- * - Mutual neighbour elimination: find two squares A,B and a
- * number N in the possible set of A, such that putting N in A
- * would rule out enough possibilities from the mutual
- * neighbours of A and B that there would be no possibilities
- * left for B. Thereby rule out N in A.
- * + The simplest case of this is if B has two possibilities
- * (wlog {1,2}), and there are two mutual neighbours of A and
- * B which have possibilities {1,3} and {2,3}. Thus, if A
- * were to be 3, then those neighbours would contain 1 and 2,
- * and hence there would be nothing left which could go in B.
- * + There can be more complex cases of it too: if A and B are
- * in the same column of large blocks, then they can have
- * more than two mutual neighbours, some of which can also be
- * neighbours of one another. Suppose, for example, that B
- * has possibilities {1,2,3}; there's one square P in the
- * same column as B and the same block as A, with
- * possibilities {1,4}; and there are _two_ squares Q,R in
- * the same column as A and the same block as B with
- * possibilities {2,3,4}. Then if A contained 4, P would
- * contain 1, and Q and R would have to contain 2 and 3 in
- * _some_ order; therefore, once again, B would have no
- * remaining possibilities.
+ * - Forcing chains (see comment for solver_forcing().)
*
* - Recursion. If all else fails, we pick one of the currently
* most constrained empty squares and take a random guess at its
* get any further.
*/
-/*
- * Within this solver, I'm going to transform all y-coordinates by
- * inverting the significance of the block number and the position
- * within the block. That is, we will start with the top row of
- * each block in order, then the second row of each block in order,
- * etc.
- *
- * This transformation has the enormous advantage that it means
- * every row, column _and_ block is described by an arithmetic
- * progression of coordinates within the cubic array, so that I can
- * use the same very simple function to do blockwise, row-wise and
- * column-wise elimination.
- */
-#define YTRANS(y) (((y)%c)*r+(y)/c)
-#define YUNTRANS(y) (((y)%r)*c+(y)/r)
-
struct solver_usage {
- int c, r, cr;
+ int cr;
+ struct block_structure *blocks;
/*
* We set up a cubic array, indexed by x, y and digit; each
* element of this array is TRUE or FALSE according to whether
* or not that digit _could_ in principle go in that position.
*
- * The way to index this array is cube[(x*cr+y)*cr+n-1].
- * y-coordinates in here are transformed.
+ * The way to index this array is cube[(y*cr+x)*cr+n-1]; there
+ * are macros below to help with this.
*/
unsigned char *cube;
/*
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) */
+ /* blk[i*cr+n-1] TRUE if digit n has been placed in block i */
unsigned char *blk;
+ /* diag[i*cr+n-1] TRUE if digit n has been placed in diagonal i */
+ unsigned char *diag; /* diag 0 is \, 1 is / */
};
-#define cubepos(x,y,n) (((x)*usage->cr+(y))*usage->cr+(n)-1)
+#define cubepos2(xy,n) ((xy)*usage->cr+(n)-1)
+#define cubepos(x,y,n) cubepos2((y)*usage->cr+(x),n)
#define cube(x,y,n) (usage->cube[cubepos(x,y,n)])
+#define cube2(xy,n) (usage->cube[cubepos2(xy,n)])
+
+#define ondiag0(xy) ((xy) % (cr+1) == 0)
+#define ondiag1(xy) ((xy) % (cr-1) == 0 && (xy) > 0 && (xy) < cr*cr-1)
+#define diag0(i) ((i) * (cr+1))
+#define diag1(i) ((i+1) * (cr-1))
/*
* Function called when we are certain that a particular square has
*/
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;
+ int cr = usage->cr;
+ int sqindex = y*cr+x;
+ int i, bi;
assert(cube(x,y,n));
/*
* Rule out this number in all other positions in the block.
*/
- bx = (x/r)*r;
- by = y % r;
- for (i = 0; i < r; i++)
- for (j = 0; j < c; j++)
- if (bx+i != x || by+j*r != y)
- cube(bx+i,by+j*r,n) = FALSE;
+ bi = usage->blocks->whichblock[sqindex];
+ for (i = 0; i < cr; i++) {
+ int bp = usage->blocks->blocks[bi][i];
+ if (bp != sqindex)
+ cube2(bp,n) = FALSE;
+ }
/*
* Enter the number in the result grid.
*/
- usage->grid[YUNTRANS(y)*cr+x] = n;
+ usage->grid[sqindex] = n;
/*
* Cross out this number from the list of numbers left to place
* in its row, its column and its block.
*/
usage->row[y*cr+n-1] = usage->col[x*cr+n-1] =
- usage->blk[((y%r)*c+(x/r))*cr+n-1] = TRUE;
+ usage->blk[bi*cr+n-1] = TRUE;
+
+ if (usage->diag) {
+ if (ondiag0(sqindex)) {
+ for (i = 0; i < cr; i++)
+ if (diag0(i) != sqindex)
+ cube2(diag0(i),n) = FALSE;
+ usage->diag[n-1] = TRUE;
+ }
+ if (ondiag1(sqindex)) {
+ for (i = 0; i < cr; i++)
+ if (diag1(i) != sqindex)
+ cube2(diag1(i),n) = FALSE;
+ usage->diag[cr+n-1] = TRUE;
+ }
+ }
}
-static int solver_elim(struct solver_usage *usage, int start, int step
+static int solver_elim(struct solver_usage *usage, int *indices
#ifdef STANDALONE_SOLVER
, char *fmt, ...
#endif
)
{
- int c = usage->c, r = usage->r, cr = c*r;
+ int cr = usage->cr;
int fpos, m, i;
/*
m = 0;
fpos = -1;
for (i = 0; i < cr; i++)
- if (usage->cube[start+i*step]) {
- fpos = start+i*step;
+ if (usage->cube[indices[i]]) {
+ fpos = indices[i];
m++;
}
assert(fpos >= 0);
n = 1 + fpos % cr;
- y = fpos / cr;
- x = y / cr;
- y %= cr;
+ x = fpos / cr;
+ y = x / cr;
+ x %= cr;
- if (!usage->grid[YUNTRANS(y)*cr+x]) {
+ if (!usage->grid[y*cr+x]) {
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
va_list ap;
vprintf(fmt, ap);
va_end(ap);
printf(":\n%*s placing %d at (%d,%d)\n",
- solver_recurse_depth*4, "", n, 1+x, 1+YUNTRANS(y));
+ solver_recurse_depth*4, "", n, 1+x, 1+y);
}
#endif
solver_place(usage, x, y, n);
}
static int solver_intersect(struct solver_usage *usage,
- int start1, int step1, int start2, int step2
+ int *indices1, int *indices2
#ifdef STANDALONE_SOLVER
, char *fmt, ...
#endif
)
{
- int c = usage->c, r = usage->r, cr = c*r;
- int ret, i;
+ int cr = usage->cr;
+ int ret, i, j;
/*
* Loop over the first domain and see if there's any set bit
* not also in the second.
*/
- for (i = 0; i < cr; i++) {
- int p = start1+i*step1;
- if (usage->cube[p] &&
- !(p >= start2 && p < start2+cr*step2 &&
- (p - start2) % step2 == 0))
- return 0; /* there is, so we can't deduce */
+ for (i = j = 0; i < cr; i++) {
+ int p = indices1[i];
+ while (j < cr && indices2[j] < p)
+ j++;
+ if (usage->cube[p]) {
+ if (j < cr && indices2[j] == p)
+ continue; /* both domains contain this index */
+ else
+ return 0; /* there is, so we can't deduce */
+ }
}
/*
* overlap; return +1 iff we actually _did_ anything.
*/
ret = 0;
- for (i = 0; i < cr; i++) {
- int p = start2+i*step2;
- if (usage->cube[p] &&
- !(p >= start1 && p < start1+cr*step1 && (p - start1) % step1 == 0))
- {
+ for (i = j = 0; i < cr; i++) {
+ int p = indices2[i];
+ while (j < cr && indices1[j] < p)
+ j++;
+ if (usage->cube[p] && (j >= cr || indices1[j] != p)) {
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
int px, py, pn;
}
pn = 1 + p % cr;
- py = p / cr;
- px = py / cr;
- py %= cr;
+ px = p / cr;
+ py = px / cr;
+ px %= cr;
printf("%*s ruling out %d at (%d,%d)\n",
- solver_recurse_depth*4, "", pn, 1+px, 1+YUNTRANS(py));
+ solver_recurse_depth*4, "", pn, 1+px, 1+py);
}
#endif
ret = +1; /* we did something */
struct solver_scratch {
unsigned char *grid, *rowidx, *colidx, *set;
int *neighbours, *bfsqueue;
+ int *indexlist, *indexlist2;
#ifdef STANDALONE_SOLVER
int *bfsprev;
#endif
static int solver_set(struct solver_usage *usage,
struct solver_scratch *scratch,
- int start, int step1, int step2
+ int *indices
#ifdef STANDALONE_SOLVER
, char *fmt, ...
#endif
)
{
- int c = usage->c, r = usage->r, cr = c*r;
+ int cr = usage->cr;
int i, j, n, count;
unsigned char *grid = scratch->grid;
unsigned char *rowidx = scratch->rowidx;
for (i = 0; i < cr; i++) {
int count = 0, first = -1;
for (j = 0; j < cr; j++)
- if (usage->cube[start+i*step1+j*step2])
+ if (usage->cube[indices[i*cr+j]])
first = j, count++;
/*
*/
for (i = 0; i < n; i++)
for (j = 0; j < n; j++)
- grid[i*cr+j] = usage->cube[start+rowidx[i]*step1+colidx[j]*step2];
+ grid[i*cr+j] = usage->cube[indices[rowidx[i]*cr+colidx[j]]];
/*
* Having done that, we now have a matrix in which every row
if (!ok) {
for (j = 0; j < n; j++)
if (!set[j] && grid[i*cr+j]) {
- int fpos = (start+rowidx[i]*step1+
- colidx[j]*step2);
+ int fpos = indices[rowidx[i]*cr+colidx[j]];
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
int px, py, pn;
}
pn = 1 + fpos % cr;
- py = fpos / cr;
- px = py / cr;
- py %= cr;
+ px = fpos / cr;
+ py = px / cr;
+ px %= cr;
printf("%*s ruling out %d at (%d,%d)\n",
solver_recurse_depth*4, "",
- pn, 1+px, 1+YUNTRANS(py));
+ pn, 1+px, 1+py);
}
#endif
progress = TRUE;
}
/*
- * Try to find a number in the possible set of (x1,y1) which can be
- * ruled out because it would leave no possibilities for (x2,y2).
- */
-static int solver_mne(struct solver_usage *usage,
- struct solver_scratch *scratch,
- int x1, int y1, int x2, int y2)
-{
- int c = usage->c, r = usage->r, cr = c*r;
- int *nb[2];
- unsigned char *set = scratch->set;
- unsigned char *numbers = scratch->rowidx;
- unsigned char *numbersleft = scratch->colidx;
- int nnb, count;
- int i, j, n, nbi;
-
- nb[0] = scratch->neighbours;
- nb[1] = scratch->neighbours + cr;
-
- /*
- * First, work out the mutual neighbour squares of the two. We
- * can assert that they're not actually in the same block,
- * which leaves two possibilities: they're in different block
- * rows _and_ different block columns (thus their mutual
- * neighbours are precisely the other two corners of the
- * rectangle), or they're in the same row (WLOG) and different
- * columns, in which case their mutual neighbours are the
- * column of each block aligned with the other square.
- *
- * We divide the mutual neighbours into two separate subsets
- * nb[0] and nb[1]; squares in the same subset are not only
- * adjacent to both our key squares, but are also always
- * adjacent to one another.
- */
- if (x1 / r != x2 / r && y1 % r != y2 % r) {
- /* Corners of the rectangle. */
- nnb = 1;
- nb[0][0] = cubepos(x2, y1, 1);
- nb[1][0] = cubepos(x1, y2, 1);
- } else if (x1 / r != x2 / r) {
- /* Same row of blocks; different blocks within that row. */
- int x1b = x1 - (x1 % r);
- int x2b = x2 - (x2 % r);
-
- nnb = r;
- for (i = 0; i < r; i++) {
- nb[0][i] = cubepos(x2b+i, y1, 1);
- nb[1][i] = cubepos(x1b+i, y2, 1);
- }
- } else {
- /* Same column of blocks; different blocks within that column. */
- int y1b = y1 % r;
- int y2b = y2 % r;
-
- assert(y1 % r != y2 % r);
-
- nnb = c;
- for (i = 0; i < c; i++) {
- nb[0][i] = cubepos(x2, y1b+i*r, 1);
- nb[1][i] = cubepos(x1, y2b+i*r, 1);
- }
- }
-
- /*
- * Right. Now loop over each possible number.
- */
- for (n = 1; n <= cr; n++) {
- if (!cube(x1, y1, n))
- continue;
- for (j = 0; j < cr; j++)
- numbersleft[j] = cube(x2, y2, j+1);
-
- /*
- * Go over every possible subset of each neighbour list,
- * and see if its union of possible numbers minus n has the
- * same size as the subset. If so, add the numbers in that
- * subset to the set of things which would be ruled out
- * from (x2,y2) if n were placed at (x1,y1).
- */
- memset(set, 0, nnb);
- count = 0;
- while (1) {
- /*
- * Binary increment: change the rightmost 0 to a 1, and
- * change all 1s to the right of it to 0s.
- */
- i = nnb;
- while (i > 0 && set[i-1])
- set[--i] = 0, count--;
- if (i > 0)
- set[--i] = 1, count++;
- else
- break; /* done */
-
- /*
- * Examine this subset of each neighbour set.
- */
- for (nbi = 0; nbi < 2; nbi++) {
- int *nbs = nb[nbi];
-
- memset(numbers, 0, cr);
-
- for (i = 0; i < nnb; i++)
- if (set[i])
- for (j = 0; j < cr; j++)
- if (j != n-1 && usage->cube[nbs[i] + j])
- numbers[j] = 1;
-
- for (i = j = 0; j < cr; j++)
- i += numbers[j];
-
- if (i == count) {
- /*
- * Got one. This subset of nbs, in the absence
- * of n, would definitely contain all the
- * numbers listed in `numbers'. Rule them out
- * of `numbersleft'.
- */
- for (j = 0; j < cr; j++)
- if (numbers[j])
- numbersleft[j] = 0;
- }
- }
- }
-
- /*
- * If we've got nothing left in `numbersleft', we have a
- * successful mutual neighbour elimination.
- */
- for (j = 0; j < cr; j++)
- if (numbersleft[j])
- break;
-
- if (j == cr) {
-#ifdef STANDALONE_SOLVER
- if (solver_show_working) {
- printf("%*smutual neighbour elimination, (%d,%d) vs (%d,%d):\n",
- solver_recurse_depth*4, "",
- 1+x1, 1+YUNTRANS(y1), 1+x2, 1+YUNTRANS(y2));
- printf("%*s ruling out %d at (%d,%d)\n",
- solver_recurse_depth*4, "",
- n, 1+x1, 1+YUNTRANS(y1));
- }
-#endif
- cube(x1, y1, n) = FALSE;
- return +1;
- }
- }
-
- return 0; /* nothing found */
-}
-
-/*
* Look for forcing chains. A forcing chain is a path of
* pairwise-exclusive squares (i.e. each pair of adjacent squares
* in the path are in the same row, column or block) with the
* (a) Each square on the path has precisely two possible numbers.
*
* (b) Each pair of squares which are adjacent on the path share
- * at least one possible number in common.
+ * at least one possible number in common.
*
* (c) Each square in the middle of the path shares _both_ of its
- * numbers with at least one of its neighbours (not the same
- * one with both neighbours).
+ * numbers with at least one of its neighbours (not the same
+ * one with both neighbours).
*
* These together imply that at least one of the possible number
* choices at one end of the path forces _all_ the rest of the
* numbers along the path. In order to make real use of this, we
* need further properties:
*
- * (c) Ruling out some number N from the square at one end
- * of the path forces the square at the other end to
- * take number N.
+ * (c) Ruling out some number N from the square at one end of the
+ * path forces the square at the other end to take the same
+ * number N.
*
* (d) The two end squares are both in line with some third
- * square.
+ * square.
*
* (e) That third square currently has N as a possibility.
*
static int solver_forcing(struct solver_usage *usage,
struct solver_scratch *scratch)
{
- int c = usage->c, r = usage->r, cr = c*r;
+ int cr = usage->cr;
int *bfsqueue = scratch->bfsqueue;
#ifdef STANDALONE_SOLVER
int *bfsprev = scratch->bfsprev;
number[y*cr+x] = t - n;
while (head < tail) {
- int xx, yy, nneighbours, xt, yt, xblk, i;
+ int xx, yy, nneighbours, xt, yt, i;
xx = bfsqueue[head++];
yy = xx / cr;
neighbours[nneighbours++] = yt*cr+xx;
for (xt = 0; xt < cr; xt++)
neighbours[nneighbours++] = yy*cr+xt;
- xblk = xx - (xx % r);
- for (yt = yy % r; yt < cr; yt += r)
- for (xt = xblk; xt < xblk+r; xt++)
- neighbours[nneighbours++] = yt*cr+xt;
+ xt = usage->blocks->whichblock[yy*cr+xx];
+ for (yt = 0; yt < cr; yt++)
+ neighbours[nneighbours++] = usage->blocks->blocks[xt][yt];
+ if (usage->diag) {
+ int sqindex = yy*cr+xx;
+ if (ondiag0(sqindex)) {
+ for (i = 0; i < cr; i++)
+ neighbours[nneighbours++] = diag0(i);
+ }
+ if (ondiag1(sqindex)) {
+ for (i = 0; i < cr; i++)
+ neighbours[nneighbours++] = diag1(i);
+ }
+ }
/*
* Try visiting each of those neighbours.
*/
if (currn == orign &&
(xt == x || yt == y ||
- (xt / r == x / r && yt % r == y % r))) {
+ (usage->blocks->whichblock[yt*cr+xt] == usage->blocks->whichblock[y*cr+x]) ||
+ (usage->diag && ((ondiag0(yt*cr+xt) && ondiag0(y*cr+x)) ||
+ (ondiag1(yt*cr+xt) && ondiag1(y*cr+x)))))) {
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
char *sep = "";
yl = yy;
while (1) {
printf("%s(%d,%d)", sep, 1+xl,
- 1+YUNTRANS(yl));
+ 1+yl);
xl = bfsprev[yl*cr+xl];
if (xl < 0)
break;
}
printf("\n%*s ruling out %d at (%d,%d)\n",
solver_recurse_depth*4, "",
- orign, 1+xt, 1+YUNTRANS(yt));
+ orign, 1+xt, 1+yt);
}
#endif
cube(xt, yt, orign) = FALSE;
scratch->rowidx = snewn(cr, unsigned char);
scratch->colidx = snewn(cr, unsigned char);
scratch->set = snewn(cr, unsigned char);
- scratch->neighbours = snewn(3*cr, int);
+ scratch->neighbours = snewn(5*cr, int);
scratch->bfsqueue = snewn(cr*cr, int);
#ifdef STANDALONE_SOLVER
scratch->bfsprev = snewn(cr*cr, int);
#endif
+ scratch->indexlist = snewn(cr*cr, int); /* used for set elimination */
+ scratch->indexlist2 = snewn(cr, int); /* only used for intersect() */
return scratch;
}
sfree(scratch->colidx);
sfree(scratch->rowidx);
sfree(scratch->grid);
+ sfree(scratch->indexlist);
+ sfree(scratch->indexlist2);
sfree(scratch);
}
-static int solver(int c, int r, digit *grid, int maxdiff)
+static int solver(int cr, struct block_structure *blocks, int xtype,
+ digit *grid, int maxdiff)
{
struct solver_usage *usage;
struct solver_scratch *scratch;
- int cr = c*r;
- int x, y, x2, y2, n, ret;
+ int x, y, b, i, n, ret;
int diff = DIFF_BLOCK;
/*
* possible).
*/
usage = snew(struct solver_usage);
- usage->c = c;
- usage->r = r;
usage->cr = cr;
+ usage->blocks = blocks;
usage->cube = snewn(cr*cr*cr, unsigned char);
usage->grid = grid; /* write straight back to the input */
memset(usage->cube, TRUE, cr*cr*cr);
memset(usage->col, FALSE, cr * cr);
memset(usage->blk, FALSE, cr * cr);
+ if (xtype) {
+ usage->diag = snewn(cr * 2, unsigned char);
+ memset(usage->diag, FALSE, cr * 2);
+ } else
+ usage->diag = NULL;
+
scratch = solver_new_scratch(usage);
/*
for (x = 0; x < cr; x++)
for (y = 0; y < cr; y++)
if (grid[y*cr+x])
- solver_place(usage, x, YTRANS(y), grid[y*cr+x]);
+ solver_place(usage, x, y, grid[y*cr+x]);
/*
* Now loop over the grid repeatedly trying all permitted modes
/*
* Blockwise positional elimination.
*/
- 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]) {
- ret = solver_elim(usage, cubepos(x,y,n), r*cr
+ for (b = 0; b < cr; b++)
+ for (n = 1; n <= cr; n++)
+ if (!usage->blk[b*cr+n-1]) {
+ for (i = 0; i < cr; i++)
+ scratch->indexlist[i] = cubepos2(usage->blocks->blocks[b][i],n);
+ ret = solver_elim(usage, scratch->indexlist
#ifdef STANDALONE_SOLVER
- , "positional elimination,"
- " %d in block (%d,%d)", n, 1+x/r, 1+y
+ , "positional elimination,"
+ " %d in block %s", n,
+ usage->blocks->blocknames[b]
#endif
- );
- if (ret < 0) {
- diff = DIFF_IMPOSSIBLE;
- goto got_result;
- } else if (ret > 0) {
- 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;
for (y = 0; y < cr; y++)
for (n = 1; n <= cr; n++)
if (!usage->row[y*cr+n-1]) {
- ret = solver_elim(usage, cubepos(0,y,n), cr*cr
+ for (x = 0; x < cr; x++)
+ scratch->indexlist[x] = cubepos(x, y, n);
+ ret = solver_elim(usage, scratch->indexlist
#ifdef STANDALONE_SOLVER
, "positional elimination,"
- " %d in row %d", n, 1+YUNTRANS(y)
+ " %d in row %d", n, 1+y
#endif
);
if (ret < 0) {
for (x = 0; x < cr; x++)
for (n = 1; n <= cr; n++)
if (!usage->col[x*cr+n-1]) {
- ret = solver_elim(usage, cubepos(x,0,n), cr
+ for (y = 0; y < cr; y++)
+ scratch->indexlist[y] = cubepos(x, y, n);
+ ret = solver_elim(usage, scratch->indexlist
#ifdef STANDALONE_SOLVER
, "positional elimination,"
" %d in column %d", n, 1+x
}
/*
+ * X-diagonal positional elimination.
+ */
+ if (usage->diag) {
+ for (n = 1; n <= cr; n++)
+ if (!usage->diag[n-1]) {
+ for (i = 0; i < cr; i++)
+ scratch->indexlist[i] = cubepos2(diag0(i), n);
+ ret = solver_elim(usage, scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "positional elimination,"
+ " %d in \\-diagonal", n
+#endif
+ );
+ if (ret < 0) {
+ diff = DIFF_IMPOSSIBLE;
+ goto got_result;
+ } else if (ret > 0) {
+ diff = max(diff, DIFF_SIMPLE);
+ goto cont;
+ }
+ }
+ for (n = 1; n <= cr; n++)
+ if (!usage->diag[cr+n-1]) {
+ for (i = 0; i < cr; i++)
+ scratch->indexlist[i] = cubepos2(diag1(i), n);
+ ret = solver_elim(usage, scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "positional elimination,"
+ " %d in /-diagonal", n
+#endif
+ );
+ if (ret < 0) {
+ diff = DIFF_IMPOSSIBLE;
+ goto got_result;
+ } else if (ret > 0) {
+ diff = max(diff, DIFF_SIMPLE);
+ goto cont;
+ }
+ }
+ }
+
+ /*
* Numeric elimination.
*/
for (x = 0; x < cr; x++)
for (y = 0; y < cr; y++)
- if (!usage->grid[YUNTRANS(y)*cr+x]) {
- ret = solver_elim(usage, cubepos(x,y,1), 1
+ if (!usage->grid[y*cr+x]) {
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[n-1] = cubepos(x, y, n);
+ ret = solver_elim(usage, scratch->indexlist
#ifdef STANDALONE_SOLVER
- , "numeric elimination at (%d,%d)", 1+x,
- 1+YUNTRANS(y)
+ , "numeric elimination at (%d,%d)",
+ 1+x, 1+y
#endif
);
if (ret < 0) {
* Intersectional analysis, rows vs blocks.
*/
for (y = 0; y < cr; y++)
- for (x = 0; x < cr; x += r)
- for (n = 1; n <= cr; n++)
+ for (b = 0; b < cr; b++)
+ for (n = 1; n <= cr; n++) {
+ if (usage->row[y*cr+n-1] ||
+ usage->blk[b*cr+n-1])
+ continue;
+ for (i = 0; i < cr; i++) {
+ scratch->indexlist[i] = cubepos(i, y, n);
+ scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n);
+ }
/*
* solver_intersect() never returns -1.
*/
- if (!usage->row[y*cr+n-1] &&
- !usage->blk[((y%r)*c+(x/r))*cr+n-1] &&
- (solver_intersect(usage, cubepos(0,y,n), cr*cr,
- cubepos(x,y%r,n), r*cr
+ if (solver_intersect(usage, scratch->indexlist,
+ scratch->indexlist2
#ifdef STANDALONE_SOLVER
, "intersectional analysis,"
- " %d in row %d vs block (%d,%d)",
- n, 1+YUNTRANS(y), 1+x/r, 1+y%r
+ " %d in row %d vs block %s",
+ n, 1+y, usage->blocks->blocknames[b]
#endif
) ||
- solver_intersect(usage, cubepos(x,y%r,n), r*cr,
- cubepos(0,y,n), cr*cr
+ solver_intersect(usage, scratch->indexlist2,
+ scratch->indexlist
#ifdef STANDALONE_SOLVER
, "intersectional analysis,"
- " %d in block (%d,%d) vs row %d",
- n, 1+x/r, 1+y%r, 1+YUNTRANS(y)
+ " %d in block %s vs row %d",
+ n, usage->blocks->blocknames[b], 1+y
#endif
- ))) {
+ )) {
diff = max(diff, DIFF_INTERSECT);
goto cont;
}
+ }
/*
* Intersectional analysis, columns vs blocks.
*/
for (x = 0; x < cr; x++)
- for (y = 0; y < r; y++)
- for (n = 1; n <= cr; n++)
- if (!usage->col[x*cr+n-1] &&
- !usage->blk[(y*c+(x/r))*cr+n-1] &&
- (solver_intersect(usage, cubepos(x,0,n), cr,
- cubepos((x/r)*r,y,n), r*cr
+ for (b = 0; b < cr; b++)
+ for (n = 1; n <= cr; n++) {
+ if (usage->col[x*cr+n-1] ||
+ usage->blk[b*cr+n-1])
+ continue;
+ for (i = 0; i < cr; i++) {
+ scratch->indexlist[i] = cubepos(x, i, n);
+ scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n);
+ }
+ if (solver_intersect(usage, scratch->indexlist,
+ scratch->indexlist2
+#ifdef STANDALONE_SOLVER
+ , "intersectional analysis,"
+ " %d in column %d vs block %s",
+ n, 1+x, usage->blocks->blocknames[b]
+#endif
+ ) ||
+ solver_intersect(usage, scratch->indexlist2,
+ scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "intersectional analysis,"
+ " %d in block %s vs column %d",
+ n, usage->blocks->blocknames[b], 1+x
+#endif
+ )) {
+ diff = max(diff, DIFF_INTERSECT);
+ goto cont;
+ }
+ }
+
+ if (usage->diag) {
+ /*
+ * Intersectional analysis, \-diagonal vs blocks.
+ */
+ for (b = 0; b < cr; b++)
+ for (n = 1; n <= cr; n++) {
+ if (usage->diag[n-1] ||
+ usage->blk[b*cr+n-1])
+ continue;
+ for (i = 0; i < cr; i++) {
+ scratch->indexlist[i] = cubepos2(diag0(i), n);
+ scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n);
+ }
+ if (solver_intersect(usage, scratch->indexlist,
+ scratch->indexlist2
+#ifdef STANDALONE_SOLVER
+ , "intersectional analysis,"
+ " %d in \\-diagonal vs block %s",
+ n, 1+x, usage->blocks->blocknames[b]
+#endif
+ ) ||
+ solver_intersect(usage, scratch->indexlist2,
+ scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "intersectional analysis,"
+ " %d in block %s vs \\-diagonal",
+ n, usage->blocks->blocknames[b], 1+x
+#endif
+ )) {
+ diff = max(diff, DIFF_INTERSECT);
+ goto cont;
+ }
+ }
+
+ /*
+ * Intersectional analysis, /-diagonal vs blocks.
+ */
+ for (b = 0; b < cr; b++)
+ for (n = 1; n <= cr; n++) {
+ if (usage->diag[cr+n-1] ||
+ usage->blk[b*cr+n-1])
+ continue;
+ for (i = 0; i < cr; i++) {
+ scratch->indexlist[i] = cubepos2(diag1(i), n);
+ scratch->indexlist2[i] = cubepos2(usage->blocks->blocks[b][i], n);
+ }
+ if (solver_intersect(usage, scratch->indexlist,
+ scratch->indexlist2
#ifdef STANDALONE_SOLVER
, "intersectional analysis,"
- " %d in column %d vs block (%d,%d)",
- n, 1+x, 1+x/r, 1+y
+ " %d in /-diagonal vs block %s",
+ n, 1+x, usage->blocks->blocknames[b]
#endif
) ||
- solver_intersect(usage, cubepos((x/r)*r,y,n), r*cr,
- cubepos(x,0,n), cr
+ solver_intersect(usage, scratch->indexlist2,
+ scratch->indexlist
#ifdef STANDALONE_SOLVER
, "intersectional analysis,"
- " %d in block (%d,%d) vs column %d",
- n, 1+x/r, 1+y, 1+x
+ " %d in block %s vs /-diagonal",
+ n, usage->blocks->blocknames[b], 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++) {
- ret = solver_set(usage, scratch, cubepos(x,y,1), r*cr, 1
+ for (b = 0; b < cr; b++) {
+ for (i = 0; i < cr; i++)
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[i*cr+n-1] = cubepos2(usage->blocks->blocks[b][i], n);
+ ret = solver_set(usage, scratch, scratch->indexlist
#ifdef STANDALONE_SOLVER
- , "set elimination, block (%d,%d)", 1+x/r, 1+y
+ , "set elimination, block %s",
+ usage->blocks->blocknames[b]
#endif
);
- if (ret < 0) {
- diff = DIFF_IMPOSSIBLE;
- goto got_result;
- } else if (ret > 0) {
- 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++) {
- ret = solver_set(usage, scratch, cubepos(0,y,1), cr*cr, 1
+ for (x = 0; x < cr; x++)
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[x*cr+n-1] = cubepos(x, y, n);
+ ret = solver_set(usage, scratch, scratch->indexlist
#ifdef STANDALONE_SOLVER
- , "set elimination, row %d", 1+YUNTRANS(y)
+ , "set elimination, row %d", 1+y
#endif
);
if (ret < 0) {
* Column-wise set elimination.
*/
for (x = 0; x < cr; x++) {
- ret = solver_set(usage, scratch, cubepos(x,0,1), cr, 1
+ for (y = 0; y < cr; y++)
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[y*cr+n-1] = cubepos(x, y, n);
+ ret = solver_set(usage, scratch, scratch->indexlist
#ifdef STANDALONE_SOLVER
, "set elimination, column %d", 1+x
#endif
}
}
+ if (usage->diag) {
+ /*
+ * \-diagonal set elimination.
+ */
+ for (i = 0; i < cr; i++)
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[i*cr+n-1] = cubepos2(diag0(i), n);
+ ret = solver_set(usage, scratch, scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "set elimination, \\-diagonal"
+#endif
+ );
+ if (ret < 0) {
+ diff = DIFF_IMPOSSIBLE;
+ goto got_result;
+ } else if (ret > 0) {
+ diff = max(diff, DIFF_SET);
+ goto cont;
+ }
+
+ /*
+ * /-diagonal set elimination.
+ */
+ for (i = 0; i < cr; i++)
+ for (n = 1; n <= cr; n++)
+ scratch->indexlist[i*cr+n-1] = cubepos2(diag1(i), n);
+ ret = solver_set(usage, scratch, scratch->indexlist
+#ifdef STANDALONE_SOLVER
+ , "set elimination, \\-diagonal"
+#endif
+ );
+ if (ret < 0) {
+ diff = DIFF_IMPOSSIBLE;
+ goto got_result;
+ } else if (ret > 0) {
+ diff = max(diff, DIFF_SET);
+ goto cont;
+ }
+ }
+
+ if (maxdiff <= DIFF_SET)
+ break;
+
/*
* Row-vs-column set elimination on a single number.
*/
for (n = 1; n <= cr; n++) {
- ret = solver_set(usage, scratch, cubepos(0,0,n), cr*cr, cr
+ for (y = 0; y < cr; y++)
+ for (x = 0; x < cr; x++)
+ scratch->indexlist[y*cr+x] = cubepos(x, y, n);
+ ret = solver_set(usage, scratch, scratch->indexlist
#ifdef STANDALONE_SOLVER
, "positional set elimination, number %d", n
#endif
}
}
- /*
- * Mutual neighbour elimination.
- */
- for (y = 0; y+1 < cr; y++) {
- for (x = 0; x+1 < cr; x++) {
- for (y2 = y+1; y2 < cr; y2++) {
- for (x2 = x+1; x2 < cr; x2++) {
- /*
- * Can't do mutual neighbour elimination
- * between elements of the same actual
- * block.
- */
- if (x/r == x2/r && y%r == y2%r)
- continue;
-
- /*
- * Otherwise, try (x,y) vs (x2,y2) in both
- * directions, and likewise (x2,y) vs
- * (x,y2).
- */
- if (!usage->grid[YUNTRANS(y)*cr+x] &&
- !usage->grid[YUNTRANS(y2)*cr+x2] &&
- (solver_mne(usage, scratch, x, y, x2, y2) ||
- solver_mne(usage, scratch, x2, y2, x, y))) {
- diff = max(diff, DIFF_EXTREME);
- goto cont;
- }
- if (!usage->grid[YUNTRANS(y)*cr+x2] &&
- !usage->grid[YUNTRANS(y2)*cr+x] &&
- (solver_mne(usage, scratch, x2, y, x, y2) ||
- solver_mne(usage, scratch, x, y2, x2, y))) {
- diff = max(diff, DIFF_EXTREME);
- goto cont;
- }
- }
- }
- }
- }
-
/*
* Forcing chains.
*/
*/
count = 0;
for (n = 1; n <= cr; n++)
- if (cube(x,YTRANS(y),n))
+ if (cube(x,y,n))
count++;
/*
/* Make a list of the possible digits. */
for (j = 0, n = 1; n <= cr; n++)
- if (cube(x,YTRANS(y),n))
+ if (cube(x,y,n))
list[j++] = n;
#ifdef STANDALONE_SOLVER
solver_recurse_depth++;
#endif
- ret = solver(c, r, outgrid, maxdiff);
+ ret = solver(cr, blocks, xtype, outgrid, maxdiff);
#ifdef STANDALONE_SOLVER
solver_recurse_depth--;
*/
struct gridgen_coord { int x, y, r; };
struct gridgen_usage {
- int c, r, cr; /* cr == c*r */
+ int cr;
+ struct block_structure *blocks;
/* 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 *col;
/* blk[(y*c+x)*cr+n-1] TRUE if digit n has been placed in block (x,y) */
unsigned char *blk;
+ /* diag[i*cr+n-1] TRUE if digit n has been placed in diagonal i */
+ unsigned char *diag;
/* This lists all the empty spaces remaining in the grid. */
struct gridgen_coord *spaces;
int nspaces;
/*
* The real recursive step in the generating function.
+ *
+ * Return values: 1 means solution found, 0 means no solution
+ * found on this branch.
*/
static int gridgen_real(struct gridgen_usage *usage, digit *grid)
{
- int c = usage->c, r = usage->r, cr = usage->cr;
+ int cr = usage->cr;
int i, j, n, sx, sy, bestm, bestr, ret;
int *digits;
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])
+ !usage->blk[usage->blocks->whichblock[y*cr+x]*cr+n] &&
+ (!usage->diag || ((!ondiag0(y*cr+x) || !usage->diag[n]) &&
+ (!ondiag1(y*cr+x) || !usage->diag[cr+n]))))
m++;
if (m < bestm || (m == bestm && usage->spaces[j].r < bestr)) {
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]) {
+ !usage->blk[usage->blocks->whichblock[sy*cr+sx]*cr+n] &&
+ (!usage->diag || ((!ondiag0(sy*cr+sx) || !usage->diag[n]) &&
+ (!ondiag1(sy*cr+sx) || !usage->diag[cr+n])))) {
digits[j++] = n+1;
}
/* 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->blk[usage->blocks->whichblock[sy*cr+sx]*cr+n-1] = TRUE;
+ if (usage->diag) {
+ if (ondiag0(sy*cr+sx))
+ usage->diag[n-1] = TRUE;
+ if (ondiag1(sy*cr+sx))
+ usage->diag[cr+n-1] = TRUE;
+ }
usage->grid[sy*cr+sx] = n;
usage->nspaces--;
/* 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->blk[usage->blocks->whichblock[sy*cr+sx]*cr+n-1] = FALSE;
+ if (usage->diag) {
+ if (ondiag0(sy*cr+sx))
+ usage->diag[n-1] = FALSE;
+ if (ondiag1(sy*cr+sx))
+ usage->diag[cr+n-1] = FALSE;
+ }
usage->grid[sy*cr+sx] = 0;
usage->nspaces++;
}
/*
- * Entry point to generator. You give it dimensions and a starting
+ * Entry point to generator. You give it parameters 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)
+static int gridgen(int cr, struct block_structure *blocks, int xtype,
+ digit *grid, random_state *rs)
{
struct gridgen_usage *usage;
- int x, y, cr = c*r;
+ int x, y, ret;
/*
* Clear the grid to start with.
*/
usage = snew(struct gridgen_usage);
- usage->c = c;
- usage->r = r;
usage->cr = cr;
+ usage->blocks = blocks;
usage->grid = snewn(cr * cr, digit);
memcpy(usage->grid, grid, cr * cr);
memset(usage->col, FALSE, cr * cr);
memset(usage->blk, FALSE, cr * cr);
+ if (xtype) {
+ usage->diag = snewn(2 * cr, unsigned char);
+ memset(usage->diag, FALSE, 2 * cr);
+ } else {
+ usage->diag = NULL;
+ }
+
usage->spaces = snewn(cr * cr, struct gridgen_coord);
usage->nspaces = 0;
/*
* Run the real generator function.
*/
- gridgen_real(usage, grid);
+ ret = gridgen_real(usage, grid);
/*
* Clean up the usage structure now we have our answer.
sfree(usage->row);
sfree(usage->grid);
sfree(usage);
+
+ return ret;
}
/* ----------------------------------------------------------------------
/*
* Check whether a grid contains a valid complete puzzle.
*/
-static int check_valid(int c, int r, digit *grid)
+static int check_valid(int cr, struct block_structure *blocks, int xtype,
+ digit *grid)
{
- int cr = c*r;
unsigned char *used;
- int x, y, n;
+ int x, y, i, j, n;
used = snewn(cr, unsigned char);
/*
* Check that each block contains precisely one of everything.
*/
- for (x = 0; x < cr; x += r) {
- for (y = 0; y < cr; y += c) {
- int xx, yy;
- memset(used, FALSE, cr);
- for (xx = x; xx < x+r; xx++)
- for (yy = 0; yy < y+c; yy++)
- if (grid[yy*cr+xx] > 0 && grid[yy*cr+xx] <= cr)
- used[grid[yy*cr+xx]-1] = TRUE;
- for (n = 0; n < cr; n++)
- if (!used[n]) {
- sfree(used);
- return FALSE;
- }
- }
+ for (i = 0; i < cr; i++) {
+ memset(used, FALSE, cr);
+ for (j = 0; j < cr; j++)
+ if (grid[blocks->blocks[i][j]] > 0 &&
+ grid[blocks->blocks[i][j]] <= cr)
+ used[grid[blocks->blocks[i][j]]-1] = TRUE;
+ for (n = 0; n < cr; n++)
+ if (!used[n]) {
+ sfree(used);
+ return FALSE;
+ }
}
- sfree(used);
- return TRUE;
+ /*
+ * Check that each diagonal contains precisely one of everything.
+ */
+ if (xtype) {
+ memset(used, FALSE, cr);
+ for (i = 0; i < cr; i++)
+ if (grid[diag0(i)] > 0 && grid[diag0(i)] <= cr)
+ used[grid[diag0(i)]-1] = TRUE;
+ for (n = 0; n < cr; n++)
+ if (!used[n]) {
+ sfree(used);
+ return FALSE;
+ }
+ for (i = 0; i < cr; i++)
+ if (grid[diag1(i)] > 0 && grid[diag1(i)] <= cr)
+ used[grid[diag1(i)]-1] = TRUE;
+ for (n = 0; n < cr; n++)
+ if (!used[n]) {
+ sfree(used);
+ return FALSE;
+ }
+ }
+
+ sfree(used);
+ return TRUE;
}
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 area = cr*cr;
+ struct block_structure *blocks;
digit *grid, *grid2;
struct xy { int x, y; } *locs;
int nlocs;
locs = snewn(area, struct xy);
grid2 = snewn(area, digit);
+ blocks = snew(struct block_structure);
+ blocks->c = params->c; blocks->r = params->r;
+ blocks->whichblock = snewn(area*2, int);
+ blocks->blocks = snewn(cr, int *);
+ for (i = 0; i < cr; i++)
+ blocks->blocks[i] = blocks->whichblock + area + i*cr;
+#ifdef STANDALONE_SOLVER
+ assert(!"This should never happen, so we don't need to create blocknames");
+#endif
+
/*
* 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 {
+ while (1) {
/*
- * Generate a random solved state.
+ * Generate a random solved state, starting by
+ * constructing the block structure.
*/
- gridgen(c, r, grid, rs);
- assert(check_valid(c, r, grid));
+ if (r == 1) { /* jigsaw mode */
+ int *dsf = divvy_rectangle(cr, cr, cr, rs);
+ int nb = 0;
+
+ for (i = 0; i < area; i++)
+ blocks->whichblock[i] = -1;
+ for (i = 0; i < area; i++) {
+ int j = dsf_canonify(dsf, i);
+ if (blocks->whichblock[j] < 0)
+ blocks->whichblock[j] = nb++;
+ blocks->whichblock[i] = blocks->whichblock[j];
+ }
+ assert(nb == cr);
+
+ sfree(dsf);
+ } else { /* basic Sudoku mode */
+ for (y = 0; y < cr; y++)
+ for (x = 0; x < cr; x++)
+ blocks->whichblock[y*cr+x] = (y/c) * c + (x/r);
+ }
+ for (i = 0; i < cr; i++)
+ blocks->blocks[i][cr-1] = 0;
+ for (i = 0; i < area; i++) {
+ int b = blocks->whichblock[i];
+ j = blocks->blocks[b][cr-1]++;
+ assert(j < cr);
+ blocks->blocks[b][j] = i;
+ }
+
+ if (!gridgen(cr, blocks, params->xtype, grid, rs))
+ continue; /* this might happen if the jigsaw is unsuitable */
+ assert(check_valid(cr, blocks, params->xtype, grid));
/*
* Save the solved grid in aux.
for (j = 0; j < ncoords; j++)
grid2[coords[2*j+1]*cr+coords[2*j]] = 0;
- ret = solver(c, r, grid2, maxdiff);
+ ret = solver(cr, blocks, params->xtype, grid2, maxdiff);
if (ret <= maxdiff) {
for (j = 0; j < ncoords; j++)
grid[coords[2*j+1]*cr+coords[2*j]] = 0;
}
memcpy(grid2, grid, area);
- } while (solver(c, r, grid2, maxdiff) < maxdiff);
+
+ if (solver(cr, blocks, params->xtype, grid2, maxdiff) == maxdiff)
+ break; /* found one! */
+ }
sfree(grid2);
sfree(locs);
char *p;
int run, i;
- desc = snewn(5 * area, char);
+ desc = snewn(7 * area, char);
p = desc;
run = 0;
for (i = 0; i <= area; i++) {
run = 0;
}
}
- assert(p - desc < 5 * area);
+
+ if (r == 1) {
+ int currrun = 0;
+
+ *p++ = ',';
+
+ /*
+ * Encode the block structure. We do this by encoding
+ * the pattern of dividing lines: first we iterate
+ * over the cr*(cr-1) internal vertical grid lines in
+ * ordinary reading order, then over the cr*(cr-1)
+ * internal horizontal ones in transposed reading
+ * order.
+ *
+ * We encode the number of non-lines between the
+ * lines; _ means zero (two adjacent divisions), a
+ * means 1, ..., y means 25, and z means 25 non-lines
+ * _and no following line_ (so that za means 26, zb 27
+ * etc).
+ */
+ for (i = 0; i <= 2*cr*(cr-1); i++) {
+ int p0, p1, edge;
+
+ if (i == 2*cr*(cr-1)) {
+ edge = TRUE; /* terminating virtual edge */
+ } else {
+ if (i < cr*(cr-1)) {
+ y = i/(cr-1);
+ x = i%(cr-1);
+ p0 = y*cr+x;
+ p1 = y*cr+x+1;
+ } else {
+ x = i/(cr-1) - cr;
+ y = i%(cr-1);
+ p0 = y*cr+x;
+ p1 = (y+1)*cr+x;
+ }
+ edge = (blocks->whichblock[p0] != blocks->whichblock[p1]);
+ }
+
+ if (edge) {
+ while (currrun > 25)
+ *p++ = 'z', currrun -= 25;
+ if (currrun)
+ *p++ = 'a'-1 + currrun;
+ else
+ *p++ = '_';
+ currrun = 0;
+ } else
+ currrun++;
+ }
+ }
+
+ assert(p - desc < 7 * area);
*p++ = '\0';
desc = sresize(desc, p - desc, char);
}
static char *validate_desc(game_params *params, char *desc)
{
- int area = params->r * params->r * params->c * params->c;
+ int cr = params->c * params->r, area = cr*cr;
int squares = 0;
+ int *dsf;
- while (*desc) {
+ while (*desc && *desc != ',') {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
squares += n - 'a' + 1;
if (squares > area)
return "Too much data to fit in grid";
+ if (params->r == 1) {
+ /*
+ * Now we expect a suffix giving the jigsaw block
+ * structure. Parse it and validate that it divides the
+ * grid into the right number of regions which are the
+ * right size.
+ */
+ if (*desc != ',')
+ return "Expected jigsaw block structure in game description";
+ int pos = 0;
+
+ dsf = snew_dsf(area);
+ desc++;
+
+ while (*desc) {
+ int c, adv;
+
+ if (*desc == '_')
+ c = 0;
+ else if (*desc >= 'a' && *desc <= 'z')
+ c = *desc - 'a' + 1;
+ else {
+ sfree(dsf);
+ return "Invalid character in game description";
+ }
+ desc++;
+
+ adv = (c != 25); /* 'z' is a special case */
+
+ while (c-- > 0) {
+ int p0, p1;
+
+ /*
+ * Non-edge; merge the two dsf classes on either
+ * side of it.
+ */
+ if (pos >= 2*cr*(cr-1)) {
+ sfree(dsf);
+ return "Too much data in block structure specification";
+ } else if (pos < cr*(cr-1)) {
+ int y = pos/(cr-1);
+ int x = pos%(cr-1);
+ p0 = y*cr+x;
+ p1 = y*cr+x+1;
+ } else {
+ int x = pos/(cr-1) - cr;
+ int y = pos%(cr-1);
+ p0 = y*cr+x;
+ p1 = (y+1)*cr+x;
+ }
+ dsf_merge(dsf, p0, p1);
+
+ pos++;
+ }
+ if (adv)
+ pos++;
+ }
+
+ /*
+ * When desc is exhausted, we expect to have gone exactly
+ * one space _past_ the end of the grid, due to the dummy
+ * edge at the end.
+ */
+ if (pos != 2*cr*(cr-1)+1) {
+ sfree(dsf);
+ return "Not enough data in block structure specification";
+ }
+
+ /*
+ * Now we've got our dsf. Verify that it matches
+ * expectations.
+ */
+ {
+ int *canons, *counts;
+ int i, j, c, ncanons = 0;
+
+ canons = snewn(cr, int);
+ counts = snewn(cr, int);
+
+ for (i = 0; i < area; i++) {
+ j = dsf_canonify(dsf, i);
+
+ for (c = 0; c < ncanons; c++)
+ if (canons[c] == j) {
+ counts[c]++;
+ if (counts[c] > cr) {
+ sfree(dsf);
+ sfree(canons);
+ sfree(counts);
+ return "A jigsaw block is too big";
+ }
+ break;
+ }
+
+ if (c == ncanons) {
+ if (ncanons >= cr) {
+ sfree(dsf);
+ sfree(canons);
+ sfree(counts);
+ return "Too many distinct jigsaw blocks";
+ }
+ canons[ncanons] = j;
+ counts[ncanons] = 1;
+ ncanons++;
+ }
+ }
+
+ /*
+ * If we've managed to get through that loop without
+ * tripping either of the error conditions, then we
+ * must have partitioned the entire grid into at most
+ * cr blocks of at most cr squares each; therefore we
+ * must have _exactly_ cr blocks of _exactly_ cr
+ * squares each. I'll verify that by assertion just in
+ * case something has gone horribly wrong, but it
+ * shouldn't have been able to happen by duff input,
+ * only by a bug in the above code.
+ */
+ assert(ncanons == cr);
+ for (c = 0; c < ncanons; c++)
+ assert(counts[c] == cr);
+
+ sfree(canons);
+ sfree(counts);
+ }
+
+ sfree(dsf);
+ } else {
+ if (*desc)
+ return "Unexpected jigsaw block structure in game description";
+ }
+
return NULL;
}
int c = params->c, r = params->r, cr = c*r, area = cr * cr;
int i;
- state->c = params->c;
- state->r = params->r;
+ state->cr = cr;
+ state->xtype = params->xtype;
state->grid = snewn(area, digit);
state->pencil = snewn(area * cr, unsigned char);
state->immutable = snewn(area, unsigned char);
memset(state->immutable, FALSE, area);
+ state->blocks = snew(struct block_structure);
+ state->blocks->c = c; state->blocks->r = r;
+ state->blocks->refcount = 1;
+ state->blocks->whichblock = snewn(area*2, int);
+ state->blocks->blocks = snewn(cr, int *);
+ for (i = 0; i < cr; i++)
+ state->blocks->blocks[i] = state->blocks->whichblock + area + i*cr;
+#ifdef STANDALONE_SOLVER
+ state->blocks->blocknames = (char **)smalloc(cr*(sizeof(char *)+80));
+#endif
+
state->completed = state->cheated = FALSE;
i = 0;
- while (*desc) {
+ while (*desc && *desc != ',') {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
int run = n - 'a' + 1;
}
assert(i == area);
+ if (r == 1) {
+ int pos = 0;
+ int *dsf;
+ int nb;
+
+ assert(*desc == ',');
+
+ dsf = snew_dsf(area);
+ desc++;
+
+ while (*desc) {
+ int c, adv;
+
+ if (*desc == '_')
+ c = 0;
+ else if (*desc >= 'a' && *desc <= 'z')
+ c = *desc - 'a' + 1;
+ else
+ assert(!"Shouldn't get here");
+ desc++;
+
+ adv = (c != 25); /* 'z' is a special case */
+
+ while (c-- > 0) {
+ int p0, p1;
+
+ /*
+ * Non-edge; merge the two dsf classes on either
+ * side of it.
+ */
+ assert(pos < 2*cr*(cr-1));
+ if (pos < cr*(cr-1)) {
+ int y = pos/(cr-1);
+ int x = pos%(cr-1);
+ p0 = y*cr+x;
+ p1 = y*cr+x+1;
+ } else {
+ int x = pos/(cr-1) - cr;
+ int y = pos%(cr-1);
+ p0 = y*cr+x;
+ p1 = (y+1)*cr+x;
+ }
+ dsf_merge(dsf, p0, p1);
+
+ pos++;
+ }
+ if (adv)
+ pos++;
+ }
+
+ /*
+ * When desc is exhausted, we expect to have gone exactly
+ * one space _past_ the end of the grid, due to the dummy
+ * edge at the end.
+ */
+ assert(pos == 2*cr*(cr-1)+1);
+
+ /*
+ * Now we've got our dsf. Translate it into a block
+ * structure.
+ */
+ nb = 0;
+ for (i = 0; i < area; i++)
+ state->blocks->whichblock[i] = -1;
+ for (i = 0; i < area; i++) {
+ int j = dsf_canonify(dsf, i);
+ if (state->blocks->whichblock[j] < 0)
+ state->blocks->whichblock[j] = nb++;
+ state->blocks->whichblock[i] = state->blocks->whichblock[j];
+ }
+ assert(nb == cr);
+
+ sfree(dsf);
+ } else {
+ int x, y;
+
+ assert(!*desc);
+
+ for (y = 0; y < cr; y++)
+ for (x = 0; x < cr; x++)
+ state->blocks->whichblock[y*cr+x] = (y/c) * c + (x/r);
+ }
+
+ /*
+ * Having sorted out whichblock[], set up the block index arrays.
+ */
+ for (i = 0; i < cr; i++)
+ state->blocks->blocks[i][cr-1] = 0;
+ for (i = 0; i < area; i++) {
+ int b = state->blocks->whichblock[i];
+ int j = state->blocks->blocks[b][cr-1]++;
+ assert(j < cr);
+ state->blocks->blocks[b][j] = i;
+ }
+
+#ifdef STANDALONE_SOLVER
+ /*
+ * Set up the block names for solver diagnostic output.
+ */
+ {
+ char *p = (char *)(state->blocks->blocknames + cr);
+
+ if (r == 1) {
+ for (i = 0; i < cr; i++)
+ state->blocks->blocknames[i] = NULL;
+
+ for (i = 0; i < area; i++) {
+ int j = state->blocks->whichblock[i];
+ if (!state->blocks->blocknames[j]) {
+ state->blocks->blocknames[j] = p;
+ p += 1 + sprintf(p, "starting at (%d,%d)",
+ 1 + i%cr, 1 + i/cr);
+ }
+ }
+ } else {
+ int bx, by;
+ for (by = 0; by < r; by++)
+ for (bx = 0; bx < c; bx++) {
+ state->blocks->blocknames[by*c+bx] = p;
+ p += 1 + sprintf(p, "(%d,%d)", bx+1, by+1);
+ }
+ }
+ assert(p - (char *)state->blocks->blocknames < cr*(sizeof(char *)+80));
+ for (i = 0; i < cr; i++)
+ assert(state->blocks->blocknames[i]);
+ }
+#endif
+
return state;
}
static game_state *dup_game(game_state *state)
{
game_state *ret = snew(game_state);
- int c = state->c, r = state->r, cr = c*r, area = cr * cr;
+ int cr = state->cr, area = cr * cr;
- ret->c = state->c;
- ret->r = state->r;
+ ret->cr = state->cr;
+ ret->xtype = state->xtype;
+
+ ret->blocks = state->blocks;
+ ret->blocks->refcount++;
ret->grid = snewn(area, digit);
memcpy(ret->grid, state->grid, area);
static void free_game(game_state *state)
{
+ if (--state->blocks->refcount == 0) {
+ sfree(state->blocks->whichblock);
+ sfree(state->blocks->blocks);
+#ifdef STANDALONE_SOLVER
+ sfree(state->blocks->blocknames);
+#endif
+ sfree(state->blocks);
+ }
sfree(state->immutable);
sfree(state->pencil);
sfree(state->grid);
static char *solve_game(game_state *state, game_state *currstate,
char *ai, char **error)
{
- int c = state->c, r = state->r, cr = c*r;
+ int cr = state->cr;
char *ret;
digit *grid;
int solve_ret;
grid = snewn(cr*cr, digit);
memcpy(grid, state->grid, cr*cr);
- solve_ret = solver(c, r, grid, DIFF_RECURSIVE);
+ solve_ret = solver(cr, state->blocks, state->xtype, grid, DIFF_RECURSIVE);
*error = NULL;
return ret;
}
-static char *grid_text_format(int c, int r, digit *grid)
+static char *grid_text_format(int cr, struct block_structure *blocks,
+ int xtype, digit *grid)
{
- int cr = c*r;
+ int vmod, hmod;
int x, y;
- int maxlen;
- char *ret, *p;
+ int totallen, linelen, nlines;
+ char *ret, *p, ch;
/*
- * 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.
+ * For non-jigsaw Sudoku, we format in the way we always have,
+ * by having the digits unevenly spaced so that the dividing
+ * lines can fit in:
+ *
+ * . . | . .
+ * . . | . .
+ * ----+----
+ * . . | . .
+ * . . | . .
+ *
+ * For jigsaw puzzles, however, we must leave space between
+ * _all_ pairs of digits for an optional dividing line, so we
+ * have to move to the rather ugly
+ *
+ * . . . .
+ * ------+------
+ * . . | . .
+ * +---+
+ * . . | . | .
+ * ------+ |
+ * . . . | .
+ *
+ * We deal with both cases using the same formatting code; we
+ * simply invent a vmod value such that there's a vertical
+ * dividing line before column i iff i is divisible by vmod
+ * (so it's r in the first case and 1 in the second), and hmod
+ * likewise for horizontal dividing lines.
*/
- maxlen = (cr+r-1) * (2*cr+2*c-2);
- ret = snewn(maxlen+1, char);
- p = ret;
+ if (blocks->r != 1) {
+ vmod = blocks->r;
+ hmod = blocks->c;
+ } else {
+ vmod = hmod = 1;
+ }
+
+ /*
+ * Line length: we have cr digits, each with a space after it,
+ * and (cr-1)/vmod dividing lines, each with a space after it.
+ * The final space is replaced by a newline, but that doesn't
+ * affect the length.
+ */
+ linelen = 2*(cr + (cr-1)/vmod);
+
+ /*
+ * Number of lines: we have cr rows of digits, and (cr-1)/hmod
+ * dividing rows.
+ */
+ nlines = cr + (cr-1)/hmod;
+
+ /*
+ * Allocate the space.
+ */
+ totallen = linelen * nlines;
+ ret = snewn(totallen+1, char); /* leave room for terminating NUL */
+
+ /*
+ * Write the text.
+ */
+ 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';
- }
+ /*
+ * Row of digits.
+ */
+ for (x = 0; x < cr; x++) {
+ /*
+ * Digit.
+ */
+ digit d = grid[y*cr+x];
+
+ if (d == 0) {
+ /*
+ * Empty space: we usually write a dot, but we'll
+ * highlight spaces on the X-diagonals (in X mode)
+ * by using underscores instead.
+ */
+ if (xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x)))
+ ch = '_';
+ else
+ ch = '.';
+ } else if (d <= 9) {
+ ch = '0' + d;
+ } else {
+ ch = 'a' + d-10;
+ }
+
+ *p++ = ch;
+ if (x == cr-1) {
+ *p++ = '\n';
+ continue;
+ }
+ *p++ = ' ';
+
+ if ((x+1) % vmod)
+ continue;
+
+ /*
+ * Optional dividing line.
+ */
+ if (blocks->whichblock[y*cr+x] != blocks->whichblock[y*cr+x+1])
+ ch = '|';
+ else
+ ch = ' ';
+ *p++ = ch;
+ *p++ = ' ';
+ }
+ if (y == cr-1 || (y+1) % hmod)
+ continue;
+
+ /*
+ * Dividing row.
+ */
+ for (x = 0; x < cr; x++) {
+ int dwid;
+ int tl, tr, bl, br;
+
+ /*
+ * Division between two squares. This varies
+ * complicatedly in length.
+ */
+ dwid = 2; /* digit and its following space */
+ if (x == cr-1)
+ dwid--; /* no following space at end of line */
+ if (x > 0 && x % vmod == 0)
+ dwid++; /* preceding space after a divider */
+
+ if (blocks->whichblock[y*cr+x] != blocks->whichblock[(y+1)*cr+x])
+ ch = '-';
+ else
+ ch = ' ';
+
+ while (dwid-- > 0)
+ *p++ = ch;
+
+ if (x == cr-1) {
+ *p++ = '\n';
+ break;
+ }
+
+ if ((x+1) % vmod)
+ continue;
+
+ /*
+ * Corner square. This is:
+ * - a space if all four surrounding squares are in
+ * the same block
+ * - a vertical line if the two left ones are in one
+ * block and the two right in another
+ * - a horizontal line if the two top ones are in one
+ * block and the two bottom in another
+ * - a plus sign in all other cases. (If we had a
+ * richer character set available we could break
+ * this case up further by doing fun things with
+ * line-drawing T-pieces.)
+ */
+ tl = blocks->whichblock[y*cr+x];
+ tr = blocks->whichblock[y*cr+x+1];
+ bl = blocks->whichblock[(y+1)*cr+x];
+ br = blocks->whichblock[(y+1)*cr+x+1];
+
+ if (tl == tr && tr == bl && bl == br)
+ ch = ' ';
+ else if (tl == bl && tr == br)
+ ch = '|';
+ else if (tl == tr && bl == br)
+ ch = '-';
+ else
+ ch = '+';
+
+ *p++ = ch;
+ }
}
- assert(p - ret == maxlen);
+ assert(p - ret == totallen);
*p = '\0';
return ret;
}
static char *game_text_format(game_state *state)
{
- return grid_text_format(state->c, state->r, state->grid);
+ return grid_text_format(state->cr, state->blocks, state->xtype,
+ state->grid);
}
struct game_ui {
static void game_changed_state(game_ui *ui, game_state *oldstate,
game_state *newstate)
{
- int c = newstate->c, r = newstate->r, cr = c*r;
+ int cr = newstate->cr;
/*
* We prevent pencil-mode highlighting of a filled square. So
* if the user has just filled in a square which we had a
struct game_drawstate {
int started;
- int c, r, cr;
+ int cr, xtype;
int tilesize;
digit *grid;
unsigned char *pencil;
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 cr = state->cr;
int tx, ty;
char buf[80];
static game_state *execute_move(game_state *from, char *move)
{
- int c = from->c, r = from->r, cr = c*r;
+ int cr = from->cr;
game_state *ret;
int x, y, n;
* 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)) {
+ if (!ret->completed && check_valid(cr, ret->blocks, ret->xtype,
+ ret->grid)) {
ret->completed = TRUE;
}
}
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
+ ret[COL_XDIAGONALS * 3 + 0] = 0.9F * ret[COL_BACKGROUND * 3 + 0];
+ ret[COL_XDIAGONALS * 3 + 1] = 0.9F * ret[COL_BACKGROUND * 3 + 1];
+ ret[COL_XDIAGONALS * 3 + 2] = 0.9F * ret[COL_BACKGROUND * 3 + 2];
+
ret[COL_GRID * 3 + 0] = 0.0F;
ret[COL_GRID * 3 + 1] = 0.0F;
ret[COL_GRID * 3 + 2] = 0.0F;
ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_USER * 3 + 2] = 0.0F;
- ret[COL_HIGHLIGHT * 3 + 0] = 0.85F * ret[COL_BACKGROUND * 3 + 0];
- 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_HIGHLIGHT * 3 + 0] = 0.78F * ret[COL_BACKGROUND * 3 + 0];
+ ret[COL_HIGHLIGHT * 3 + 1] = 0.78F * ret[COL_BACKGROUND * 3 + 1];
+ ret[COL_HIGHLIGHT * 3 + 2] = 0.78F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_ERROR * 3 + 0] = 1.0F;
ret[COL_ERROR * 3 + 1] = 0.0F;
static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
{
struct game_drawstate *ds = snew(struct game_drawstate);
- int c = state->c, r = state->r, cr = c*r;
+ int cr = state->cr;
ds->started = FALSE;
- ds->c = c;
- ds->r = r;
ds->cr = cr;
+ ds->xtype = state->xtype;
ds->grid = snewn(cr*cr, digit);
- memset(ds->grid, 0, cr*cr);
+ memset(ds->grid, cr+2, cr*cr);
ds->pencil = snewn(cr*cr*cr, digit);
memset(ds->pencil, 0, cr*cr*cr);
ds->hl = snewn(cr*cr, unsigned char);
static void draw_number(drawing *dr, game_drawstate *ds, game_state *state,
int x, int y, int hl)
{
- int c = state->c, r = state->r, cr = c*r;
+ int cr = state->cr;
int tx, ty;
int cx, cy, cw, ch;
char str[2];
!memcmp(ds->pencil+(y*cr+x)*cr, state->pencil+(y*cr+x)*cr, cr))
return; /* no change required */
- tx = BORDER + x * TILE_SIZE + 2;
- ty = BORDER + y * TILE_SIZE + 2;
+ tx = BORDER + x * TILE_SIZE + 1 + GRIDEXTRA;
+ ty = BORDER + y * TILE_SIZE + 1 + GRIDEXTRA;
cx = tx;
cy = ty;
- cw = TILE_SIZE-3;
- ch = TILE_SIZE-3;
-
- if (x % r)
- cx--, cw++;
- if ((x+1) % r)
- cw++;
- if (y % c)
- cy--, ch++;
- if ((y+1) % c)
- ch++;
+ cw = TILE_SIZE-1-2*GRIDEXTRA;
+ ch = TILE_SIZE-1-2*GRIDEXTRA;
+
+ if (x > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x-1])
+ cx -= GRIDEXTRA, cw += GRIDEXTRA;
+ if (x+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[y*cr+x+1])
+ cw += GRIDEXTRA;
+ if (y > 0 && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y-1)*cr+x])
+ cy -= GRIDEXTRA, ch += GRIDEXTRA;
+ if (y+1 < cr && state->blocks->whichblock[y*cr+x] == state->blocks->whichblock[(y+1)*cr+x])
+ ch += GRIDEXTRA;
clip(dr, cx, cy, cw, ch);
/* background needs erasing */
- draw_rect(dr, cx, cy, cw, ch, (hl & 15) == 1 ? COL_HIGHLIGHT : COL_BACKGROUND);
+ draw_rect(dr, cx, cy, cw, ch,
+ ((hl & 15) == 1 ? COL_HIGHLIGHT :
+ (ds->xtype && (ondiag0(y*cr+x) || ondiag1(y*cr+x))) ? COL_XDIAGONALS :
+ COL_BACKGROUND));
+
+ /*
+ * Draw the corners of thick lines in corner-adjacent squares,
+ * which jut into this square by one pixel.
+ */
+ if (x > 0 && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x-1])
+ draw_rect(dr, tx-GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID);
+ if (x+1 < cr && y > 0 && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y-1)*cr+x+1])
+ draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty-GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID);
+ if (x > 0 && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x-1])
+ draw_rect(dr, tx-GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID);
+ if (x+1 < cr && y+1 < cr && state->blocks->whichblock[y*cr+x] != state->blocks->whichblock[(y+1)*cr+x+1])
+ draw_rect(dr, tx+TILE_SIZE-1-2*GRIDEXTRA, ty+TILE_SIZE-1-2*GRIDEXTRA, GRIDEXTRA, GRIDEXTRA, COL_GRID);
/* pencil-mode highlight */
if ((hl & 15) == 2) {
game_state *state, int dir, game_ui *ui,
float animtime, float flashtime)
{
- int c = state->c, r = state->r, cr = c*r;
+ int cr = state->cr;
int x, y;
if (!ds->started) {
draw_rect(dr, 0, 0, SIZE(cr), SIZE(cr), COL_BACKGROUND);
/*
- * Draw the grid.
+ * Draw the grid. We draw it as a big thick rectangle of
+ * COL_GRID initially; individual calls to draw_number()
+ * will poke the right-shaped holes in it.
*/
- for (x = 0; x <= cr; x++) {
- int thick = (x % r ? 0 : 1);
- draw_rect(dr, BORDER + x*TILE_SIZE - thick, BORDER-1,
- 1+2*thick, cr*TILE_SIZE+3, COL_GRID);
- }
- for (y = 0; y <= cr; y++) {
- int thick = (y % c ? 0 : 1);
- draw_rect(dr, BORDER-1, BORDER + y*TILE_SIZE - thick,
- cr*TILE_SIZE+3, 1+2*thick, COL_GRID);
- }
+ draw_rect(dr, BORDER-GRIDEXTRA, BORDER-GRIDEXTRA,
+ cr*TILE_SIZE+1+2*GRIDEXTRA, cr*TILE_SIZE+1+2*GRIDEXTRA,
+ COL_GRID);
}
/*
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;
+ int box = state->blocks->whichblock[y*cr+x];
+ 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;
+ if (ds->xtype) {
+ if (ondiag0(y*cr+x))
+ ds->entered_items[d-1] |= ((ds->entered_items[d-1] & 64) << 1) | 64;
+ if (ondiag1(y*cr+x))
+ ds->entered_items[cr+d-1] |= ((ds->entered_items[cr+d-1] & 64) << 1) | 64;
+ }
}
}
* 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)))
+ (ds->entered_items[state->blocks->whichblock[y*cr+x]*cr+d-1] & 32) ||
+ (ds->xtype && ((ondiag0(y*cr+x) && (ds->entered_items[d-1] & 128)) ||
+ (ondiag1(y*cr+x) && (ds->entered_items[cr+d-1] & 128))))))
highlight |= 16;
draw_number(dr, ds, state, x, y, highlight);
static void game_print(drawing *dr, game_state *state, int tilesize)
{
- int c = state->c, r = state->r, cr = c*r;
+ int cr = state->cr;
int ink = print_mono_colour(dr, 0);
int x, y;
draw_rect_outline(dr, BORDER, BORDER, cr*TILE_SIZE, cr*TILE_SIZE, ink);
/*
- * Grid.
+ * Highlight X-diagonal squares.
+ */
+ if (state->xtype) {
+ int i;
+ int xhighlight = print_grey_colour(dr, HATCH_SLASH, 0.90F);
+
+ for (i = 0; i < cr; i++)
+ draw_rect(dr, BORDER + i*TILE_SIZE, BORDER + i*TILE_SIZE,
+ TILE_SIZE, TILE_SIZE, xhighlight);
+ for (i = 0; i < cr; i++)
+ if (i*2 != cr-1) /* avoid redoing centre square, just for fun */
+ draw_rect(dr, BORDER + i*TILE_SIZE,
+ BORDER + (cr-1-i)*TILE_SIZE,
+ TILE_SIZE, TILE_SIZE, xhighlight);
+ }
+
+ /*
+ * Main grid.
*/
for (x = 1; x < cr; x++) {
- print_line_width(dr, (x % r ? 1 : 3) * TILE_SIZE / 40);
+ print_line_width(dr, TILE_SIZE / 40);
draw_line(dr, BORDER+x*TILE_SIZE, BORDER,
BORDER+x*TILE_SIZE, BORDER+cr*TILE_SIZE, ink);
}
for (y = 1; y < cr; y++) {
- print_line_width(dr, (y % c ? 1 : 3) * TILE_SIZE / 40);
+ print_line_width(dr, TILE_SIZE / 40);
draw_line(dr, BORDER, BORDER+y*TILE_SIZE,
BORDER+cr*TILE_SIZE, BORDER+y*TILE_SIZE, ink);
}
/*
+ * Thick lines between cells. In order to do this using the
+ * line-drawing rather than rectangle-drawing API (so as to
+ * get line thicknesses to scale correctly) and yet have
+ * correctly mitred joins between lines, we must do this by
+ * tracing the boundary of each sub-block and drawing it in
+ * one go as a single polygon.
+ */
+ {
+ int *coords;
+ int bi, i, n;
+ int x, y, dx, dy, sx, sy, sdx, sdy;
+
+ print_line_width(dr, 3 * TILE_SIZE / 40);
+
+ /*
+ * Maximum perimeter of a k-omino is 2k+2. (Proof: start
+ * with k unconnected squares, with total perimeter 4k.
+ * Now repeatedly join two disconnected components
+ * together into a larger one; every time you do so you
+ * remove at least two unit edges, and you require k-1 of
+ * these operations to create a single connected piece, so
+ * you must have at most 4k-2(k-1) = 2k+2 unit edges left
+ * afterwards.)
+ */
+ coords = snewn(4*cr+4, int); /* 2k+2 points, 2 coords per point */
+
+ /*
+ * Iterate over all the blocks.
+ */
+ for (bi = 0; bi < cr; bi++) {
+
+ /*
+ * For each block, find a starting square within it
+ * which has a boundary at the left.
+ */
+ for (i = 0; i < cr; i++) {
+ int j = state->blocks->blocks[bi][i];
+ if (j % cr == 0 || state->blocks->whichblock[j-1] != bi)
+ break;
+ }
+ assert(i < cr); /* every block must have _some_ leftmost square */
+ x = state->blocks->blocks[bi][i] % cr;
+ y = state->blocks->blocks[bi][i] / cr;
+ dx = -1;
+ dy = 0;
+
+ /*
+ * Now begin tracing round the perimeter. At all
+ * times, (x,y) describes some square within the
+ * block, and (x+dx,y+dy) is some adjacent square
+ * outside it; so the edge between those two squares
+ * is always an edge of the block.
+ */
+ sx = x, sy = y, sdx = dx, sdy = dy; /* save starting position */
+ n = 0;
+ do {
+ int cx, cy, tx, ty, nin;
+
+ /*
+ * To begin with, record the point at one end of
+ * the edge. To do this, we translate (x,y) down
+ * and right by half a unit (so they're describing
+ * a point in the _centre_ of the square) and then
+ * translate back again in a manner rotated by dy
+ * and dx.
+ */
+ assert(n < 2*cr+2);
+ cx = ((2*x+1) + dy + dx) / 2;
+ cy = ((2*y+1) - dx + dy) / 2;
+ coords[2*n+0] = BORDER + cx * TILE_SIZE;
+ coords[2*n+1] = BORDER + cy * TILE_SIZE;
+ n++;
+
+ /*
+ * Now advance to the next edge, by looking at the
+ * two squares beyond it. If they're both outside
+ * the block, we turn right (by leaving x,y the
+ * same and rotating dx,dy clockwise); if they're
+ * both inside, we turn left (by rotating dx,dy
+ * anticlockwise and contriving to leave x+dx,y+dy
+ * unchanged); if one of each, we go straight on
+ * (and may enforce by assertion that they're one
+ * of each the _right_ way round).
+ */
+ nin = 0;
+ tx = x - dy + dx;
+ ty = y + dx + dy;
+ nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr &&
+ state->blocks->whichblock[ty*cr+tx] == bi);
+ tx = x - dy;
+ ty = y + dx;
+ nin += (tx >= 0 && tx < cr && ty >= 0 && ty < cr &&
+ state->blocks->whichblock[ty*cr+tx] == bi);
+ if (nin == 0) {
+ /*
+ * Turn right.
+ */
+ int tmp;
+ tmp = dx;
+ dx = -dy;
+ dy = tmp;
+ } else if (nin == 2) {
+ /*
+ * Turn left.
+ */
+ int tmp;
+
+ x += dx;
+ y += dy;
+
+ tmp = dx;
+ dx = dy;
+ dy = -tmp;
+
+ x -= dx;
+ y -= dy;
+ } else {
+ /*
+ * Go straight on.
+ */
+ x -= dy;
+ y += dx;
+ }
+
+ /*
+ * Now enforce by assertion that we ended up
+ * somewhere sensible.
+ */
+ assert(x >= 0 && x < cr && y >= 0 && y < cr &&
+ state->blocks->whichblock[y*cr+x] == bi);
+ assert(x+dx < 0 || x+dx >= cr || y+dy < 0 || y+dy >= cr ||
+ state->blocks->whichblock[(y+dy)*cr+(x+dx)] != bi);
+
+ } while (x != sx || y != sy || dx != sdx || dy != sdy);
+
+ /*
+ * That's our polygon; now draw it.
+ */
+ draw_polygon(dr, coords, n, -1, ink);
+ }
+
+ sfree(coords);
+ }
+
+ /*
* Numbers.
*/
for (y = 0; y < cr; y++)
}
s = new_game(NULL, p, desc);
- ret = solver(p->c, p->r, s->grid, DIFF_RECURSIVE);
+ ret = solver(s->cr, s->blocks, s->xtype, s->grid, DIFF_RECURSIVE);
if (grade) {
printf("Difficulty rating: %s\n",
ret==DIFF_BLOCK ? "Trivial (blockwise positional elimination only)":
ret==DIFF_IMPOSSIBLE ? "Impossible (no solution exists)":
"INTERNAL ERROR: unrecognised difficulty code");
} else {
- printf("%s\n", grid_text_format(p->c, p->r, s->grid));
+ printf("%s\n", grid_text_format(s->cr, s->blocks, s->xtype, s->grid));
}
return 0;
~mdw / sgt / puzzles / commitdiff