ref: 26a40781e6a3d64a32f8f98529b62917dd32d389
dir: /unfinished/group.c/
/*
* group.c: a Latin-square puzzle, but played with groups' Cayley
* tables. That is, you are given a Cayley table of a group with
* most elements blank and a few clues, and you must fill it in
* so as to preserve the group axioms.
*
* This is a perfectly playable and fully working puzzle, but I'm
* leaving it for the moment in the 'unfinished' directory because
* it's just too esoteric (not to mention _hard_) for me to be
* comfortable presenting it to the general public as something they
* might (implicitly) actually want to play.
*
* TODO:
*
* - more solver techniques?
* * Inverses: once we know that gh = e, we can immediately
* deduce hg = e as well; then for any gx=y we can deduce
* hy=x, and for any xg=y we have yh=x.
* * Hard-mode associativity: we currently deduce based on
* definite numbers in the grid, but we could also winnow
* based on _possible_ numbers.
* * My overambitious original thoughts included wondering if we
* could infer that there must be elements of certain orders
* (e.g. a group of order divisible by 5 must contain an
* element of order 5), but I think in fact this is probably
* silly.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include "puzzles.h"
#include "latin.h"
/*
* Difficulty levels. I do some macro ickery here to ensure that my
* enum and the various forms of my name list always match up.
*/
#define DIFFLIST(A) \
A(TRIVIAL,Trivial,NULL,t) \
A(NORMAL,Normal,solver_normal,n) \
A(HARD,Hard,NULL,h) \
A(EXTREME,Extreme,NULL,x) \
A(UNREASONABLE,Unreasonable,NULL,u)
#define ENUM(upper,title,func,lower) DIFF_ ## upper,
#define TITLE(upper,title,func,lower) #title,
#define ENCODE(upper,title,func,lower) #lower
#define CONFIG(upper,title,func,lower) ":" #title
enum { DIFFLIST(ENUM) DIFFCOUNT };
static char const *const group_diffnames[] = { DIFFLIST(TITLE) };
static char const group_diffchars[] = DIFFLIST(ENCODE);
#define DIFFCONFIG DIFFLIST(CONFIG)
enum {
COL_BACKGROUND,
COL_GRID,
COL_USER,
COL_HIGHLIGHT,
COL_ERROR,
COL_PENCIL,
COL_DIAGONAL,
NCOLOURS
};
/*
* In identity mode, we number the elements e,a,b,c,d,f,g,h,...
* Otherwise, they're a,b,c,d,e,f,g,h,... in the obvious way.
*/
#define E_TO_FRONT(c,id) ( (id) && (c)<=5 ? (c) % 5 + 1 : (c) )
#define E_FROM_FRONT(c,id) ( (id) && (c)<=5 ? ((c) + 3) % 5 + 1 : (c) )
#define FROMCHAR(c,id) E_TO_FRONT((((c)-('A'-1)) & ~0x20), id)
#define ISCHAR(c) (((c)>='A'&&(c)<='Z') || ((c)>='a'&&(c)<='z'))
#define TOCHAR(c,id) (E_FROM_FRONT(c,id) + ('a'-1))
struct game_params {
int w, diff;
bool id;
};
typedef struct group_common {
int refcount;
bool *immutable;
} group_common;
struct game_state {
game_params par;
digit *grid;
int *pencil; /* bitmaps using bits 1<<1..1<<n */
group_common *common;
bool completed, cheated;
digit *sequence; /* sequence of group elements shown */
/*
* This array indicates thick lines separating rows and columns
* placed and unplaced manually by the user as a visual aid, e.g.
* to delineate a subgroup and its cosets.
*
* When a line is placed, it's deemed to be between the two
* particular group elements that are on either side of it at the
* time; dragging those two away from each other automatically
* gets rid of the line. Hence, for a given element i, dividers[i]
* is either -1 (indicating no divider to the right of i), or some
* other element (indicating a divider to the right of i iff that
* element is the one right of it). These are eagerly cleared
* during drags.
*/
int *dividers; /* thick lines between rows/cols */
};
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
ret->w = 6;
ret->diff = DIFF_NORMAL;
ret->id = true;
return ret;
}
const static struct game_params group_presets[] = {
{ 6, DIFF_NORMAL, true },
{ 6, DIFF_NORMAL, false },
{ 8, DIFF_NORMAL, true },
{ 8, DIFF_NORMAL, false },
{ 8, DIFF_HARD, true },
{ 8, DIFF_HARD, false },
{ 12, DIFF_NORMAL, true },
};
static bool game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
char buf[80];
if (i < 0 || i >= lenof(group_presets))
return false;
ret = snew(game_params);
*ret = group_presets[i]; /* structure copy */
sprintf(buf, "%dx%d %s%s", ret->w, ret->w, group_diffnames[ret->diff],
ret->id ? "" : ", identity hidden");
*name = dupstr(buf);
*params = ret;
return true;
}
static void free_params(game_params *params)
{
sfree(params);
}
static game_params *dup_params(const game_params *params)
{
game_params *ret = snew(game_params);
*ret = *params; /* structure copy */
return ret;
}
static void decode_params(game_params *params, char const *string)
{
char const *p = string;
params->w = atoi(p);
while (*p && isdigit((unsigned char)*p)) p++;
params->diff = DIFF_NORMAL;
params->id = true;
while (*p) {
if (*p == 'd') {
int i;
p++;
params->diff = DIFFCOUNT+1; /* ...which is invalid */
if (*p) {
for (i = 0; i < DIFFCOUNT; i++) {
if (*p == group_diffchars[i])
params->diff = i;
}
p++;
}
} else if (*p == 'i') {
params->id = false;
p++;
} else {
/* unrecognised character */
p++;
}
}
}
static char *encode_params(const game_params *params, bool full)
{
char ret[80];
sprintf(ret, "%d", params->w);
if (full)
sprintf(ret + strlen(ret), "d%c", group_diffchars[params->diff]);
if (!params->id)
sprintf(ret + strlen(ret), "i");
return dupstr(ret);
}
static config_item *game_configure(const game_params *params)
{
config_item *ret;
char buf[80];
ret = snewn(4, config_item);
ret[0].name = "Grid size";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->w);
ret[0].u.string.sval = dupstr(buf);
ret[1].name = "Difficulty";
ret[1].type = C_CHOICES;
ret[1].u.choices.choicenames = DIFFCONFIG;
ret[1].u.choices.selected = params->diff;
ret[2].name = "Show identity";
ret[2].type = C_BOOLEAN;
ret[2].u.boolean.bval = params->id;
ret[3].name = NULL;
ret[3].type = C_END;
return ret;
}
static game_params *custom_params(const config_item *cfg)
{
game_params *ret = snew(game_params);
ret->w = atoi(cfg[0].u.string.sval);
ret->diff = cfg[1].u.choices.selected;
ret->id = cfg[2].u.boolean.bval;
return ret;
}
static const char *validate_params(const game_params *params, bool full)
{
if (params->w < 3 || params->w > 26)
return "Grid size must be between 3 and 26";
if (params->diff >= DIFFCOUNT)
return "Unknown difficulty rating";
if (!params->id && params->diff == DIFF_TRIVIAL) {
/*
* We can't have a Trivial-difficulty puzzle (i.e. latin
* square deductions only) without a clear identity, because
* identityless puzzles always have two rows and two columns
* entirely blank, and no latin-square deduction permits the
* distinguishing of two such rows.
*/
return "Trivial puzzles must have an identity";
}
if (!params->id && params->w == 3) {
/*
* We can't have a 3x3 puzzle without an identity either,
* because 3x3 puzzles can't ever be harder than Trivial
* (there are no 3x3 latin squares which aren't also valid
* group tables, so enabling group-based deductions doesn't
* rule out any possible solutions) and - as above - Trivial
* puzzles can't not have an identity.
*/
return "3x3 puzzles must have an identity";
}
return NULL;
}
/* ----------------------------------------------------------------------
* Solver.
*/
static int solver_normal(struct latin_solver *solver, void *vctx)
{
int w = solver->o;
#ifdef STANDALONE_SOLVER
char **names = solver->names;
#endif
digit *grid = solver->grid;
int i, j, k;
/*
* Deduce using associativity: (ab)c = a(bc).
*
* So we pick any a,b,c we like; then if we know ab, bc, and
* (ab)c we can fill in a(bc).
*/
for (i = 1; i < w; i++)
for (j = 1; j < w; j++)
for (k = 1; k < w; k++) {
if (!grid[i*w+j] || !grid[j*w+k])
continue;
if (grid[(grid[i*w+j]-1)*w+k] &&
!grid[i*w+(grid[j*w+k]-1)]) {
int x = grid[j*w+k]-1, y = i;
int n = grid[(grid[i*w+j]-1)*w+k];
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
printf("%*sassociativity on %s,%s,%s: %s*%s = %s*%s\n",
solver_recurse_depth*4, "",
names[i], names[j], names[k],
names[grid[i*w+j]-1], names[k],
names[i], names[grid[j*w+k]-1]);
printf("%*s placing %s at (%d,%d)\n",
solver_recurse_depth*4, "",
names[n-1], x+1, y+1);
}
#endif
if (solver->cube[(x*w+y)*w+n-1]) {
latin_solver_place(solver, x, y, n);
return 1;
} else {
#ifdef STANDALONE_SOLVER
if (solver_show_working)
printf("%*s contradiction!\n",
solver_recurse_depth*4, "");
return -1;
#endif
}
}
if (!grid[(grid[i*w+j]-1)*w+k] &&
grid[i*w+(grid[j*w+k]-1)]) {
int x = k, y = grid[i*w+j]-1;
int n = grid[i*w+(grid[j*w+k]-1)];
#ifdef STANDALONE_SOLVER
if (solver_show_working) {
printf("%*sassociativity on %s,%s,%s: %s*%s = %s*%s\n",
solver_recurse_depth*4, "",
names[i], names[j], names[k],
names[grid[i*w+j]-1], names[k],
names[i], names[grid[j*w+k]-1]);
printf("%*s placing %s at (%d,%d)\n",
solver_recurse_depth*4, "",
names[n-1], x+1, y+1);
}
#endif
if (solver->cube[(x*w+y)*w+n-1]) {
latin_solver_place(solver, x, y, n);
return 1;
} else {
#ifdef STANDALONE_SOLVER
if (solver_show_working)
printf("%*s contradiction!\n",
solver_recurse_depth*4, "");
return -1;
#endif
}
}
}
return 0;
}
#define SOLVER(upper,title,func,lower) func,
static usersolver_t const group_solvers[] = { DIFFLIST(SOLVER) };
static int solver(const game_params *params, digit *grid, int maxdiff)
{
int w = params->w;
int ret;
struct latin_solver solver;
#ifdef STANDALONE_SOLVER
char *p, text[100], *names[50];
int i;
#endif
latin_solver_alloc(&solver, grid, w);
#ifdef STANDALONE_SOLVER
for (i = 0, p = text; i < w; i++) {
names[i] = p;
*p++ = TOCHAR(i+1, params->id);
*p++ = '\0';
}
solver.names = names;
#endif
ret = latin_solver_main(&solver, maxdiff,
DIFF_TRIVIAL, DIFF_HARD, DIFF_EXTREME,
DIFF_EXTREME, DIFF_UNREASONABLE,
group_solvers, NULL, NULL, NULL);
latin_solver_free(&solver);
return ret;
}
/* ----------------------------------------------------------------------
* Grid generation.
*/
static char *encode_grid(char *desc, digit *grid, int area)
{
int run, i;
char *p = desc;
run = 0;
for (i = 0; i <= area; i++) {
int n = (i < area ? grid[i] : -1);
if (!n)
run++;
else {
if (run) {
while (run > 0) {
int c = 'a' - 1 + run;
if (run > 26)
c = 'z';
*p++ = c;
run -= c - ('a' - 1);
}
} else {
/*
* If there's a number in the very top left or
* bottom right, there's no point putting an
* unnecessary _ before or after it.
*/
if (p > desc && n > 0)
*p++ = '_';
}
if (n > 0)
p += sprintf(p, "%d", n);
run = 0;
}
}
return p;
}
/* ----- data generated by group.gap begins ----- */
struct group {
unsigned long autosize;
int order, ngens;
const char *gens;
};
struct groups {
int ngroups;
const struct group *groups;
};
static const struct group groupdata[] = {
/* order 2 */
{1L, 2, 1, "BA"},
/* order 3 */
{2L, 3, 1, "BCA"},
/* order 4 */
{2L, 4, 1, "BCDA"},
{6L, 4, 2, "BADC" "CDAB"},
/* order 5 */
{4L, 5, 1, "BCDEA"},
/* order 6 */
{6L, 6, 2, "CFEBAD" "BADCFE"},
{2L, 6, 1, "DCFEBA"},
/* order 7 */
{6L, 7, 1, "BCDEFGA"},
/* order 8 */
{4L, 8, 1, "BCEFDGHA"},
{8L, 8, 2, "BDEFGAHC" "EGBHDCFA"},
{8L, 8, 2, "EGBHDCFA" "BAEFCDHG"},
{24L, 8, 2, "BDEFGAHC" "CHDGBEAF"},
{168L, 8, 3, "BAEFCDHG" "CEAGBHDF" "DFGAHBCE"},
/* order 9 */
{6L, 9, 1, "BDECGHFIA"},
{48L, 9, 2, "BDEAGHCIF" "CEFGHAIBD"},
/* order 10 */
{20L, 10, 2, "CJEBGDIFAH" "BADCFEHGJI"},
{4L, 10, 1, "DCFEHGJIBA"},
/* order 11 */
{10L, 11, 1, "BCDEFGHIJKA"},
/* order 12 */
{12L, 12, 2, "GLDKJEHCBIAF" "BCEFAGIJDKLH"},
{4L, 12, 1, "EHIJKCBLDGFA"},
{24L, 12, 2, "BEFGAIJKCDLH" "FJBKHLEGDCIA"},
{12L, 12, 2, "GLDKJEHCBIAF" "BAEFCDIJGHLK"},
{12L, 12, 2, "FDIJGHLBKAEC" "GIDKFLHCJEAB"},
/* order 13 */
{12L, 13, 1, "BCDEFGHIJKLMA"},
/* order 14 */
{42L, 14, 2, "ELGNIBKDMFAHCJ" "BADCFEHGJILKNM"},
{6L, 14, 1, "FEHGJILKNMBADC"},
/* order 15 */
{8L, 15, 1, "EGHCJKFMNIOBLDA"},
/* order 16 */
{8L, 16, 1, "MKNPFOADBGLCIEHJ"},
{96L, 16, 2, "ILKCONFPEDJHGMAB" "BDFGHIAKLMNCOEPJ"},
{32L, 16, 2, "MIHPFDCONBLAKJGE" "BEFGHJKALMNOCDPI"},
{32L, 16, 2, "IFACOGLMDEJBNPKH" "BEFGHJKALMNOCDPI"},
{16L, 16, 2, "MOHPFKCINBLADJGE" "BDFGHIEKLMNJOAPC"},
{16L, 16, 2, "MIHPFDJONBLEKCGA" "BDFGHIEKLMNJOAPC"},
{32L, 16, 2, "MOHPFDCINBLEKJGA" "BAFGHCDELMNIJKPO"},
{16L, 16, 2, "MIHPFKJONBLADCGE" "GDPHNOEKFLBCIAMJ"},
{32L, 16, 2, "MIBPFDJOGHLEKCNA" "CLEIJGMPKAOHNFDB"},
{192L, 16, 3,
"MCHPFAIJNBLDEOGK" "BEFGHJKALMNOCDPI" "GKLBNOEDFPHJIAMC"},
{64L, 16, 3, "MCHPFAIJNBLDEOGK" "LOGFPKJIBNMEDCHA" "CMAIJHPFDEONBLKG"},
{192L, 16, 3,
"IPKCOGMLEDJBNFAH" "BEFGHJKALMNOCDPI" "CMEIJBPFKAOGHLDN"},
{48L, 16, 3, "IPDJONFLEKCBGMAH" "FJBLMEOCGHPKAIND" "DGIEKLHNJOAMPBCF"},
{20160L, 16, 4,
"EHJKAMNBOCDPFGIL" "BAFGHCDELMNIJKPO" "CFAIJBLMDEOGHPKN"
"DGIAKLBNCOEFPHJM"},
/* order 17 */
{16L, 17, 1, "EFGHIJKLMNOPQABCD"},
/* order 18 */
{54L, 18, 2, "MKIQOPNAGLRECDBJHF" "BAEFCDJKLGHIOPMNRQ"},
{6L, 18, 1, "ECJKGHFOPDMNLRIQBA"},
{12L, 18, 2, "ECJKGHBOPAMNFRDQLI" "KNOPQCFREIGHLJAMBD"},
{432L, 18, 3,
"IFNAKLQCDOPBGHREMJ" "NOQCFRIGHKLJAMPBDE" "BAEFCDJKLGHIOPMNRQ"},
{48L, 18, 2, "ECJKGHBOPAMNFRDQLI" "FDKLHIOPBMNAREQCJG"},
/* order 19 */
{18L, 19, 1, "EFGHIJKLMNOPQRSABCD"},
/* order 20 */
{40L, 20, 2, "GTDKREHOBILSFMPCJQAN" "EABICDFMGHJQKLNTOPRS"},
{8L, 20, 1, "EHIJLCMNPGQRSKBTDOFA"},
{20L, 20, 2, "DJSHQNCLTRGPEBKAIFOM" "EABICDFMGHJQKLNTOPRS"},
{40L, 20, 2, "GTDKREHOBILSFMPCJQAN" "ECBIAGFMDKJQHONTLSRP"},
{24L, 20, 2, "IGFMDKJQHONTLSREPCBA" "FDIJGHMNKLQROPTBSAEC"},
/* order 21 */
{42L, 21, 2, "ITLSBOUERDHAGKCJNFMQP" "EJHLMKOPNRSQAUTCDBFGI"},
{12L, 21, 1, "EGHCJKFMNIPQLSTOUBRDA"},
/* order 22 */
{110L, 22, 2, "ETGVIBKDMFOHQJSLUNAPCR" "BADCFEHGJILKNMPORQTSVU"},
{10L, 22, 1, "FEHGJILKNMPORQTSVUBADC"},
/* order 23 */
{22L, 23, 1, "EFGHIJKLMNOPQRSTUVWABCD"},
/* order 24 */
{24L, 24, 2, "QXEJWPUMKLRIVBFTSACGHNDO" "HRNOPSWCTUVBLDIJXFGAKQME"},
{8L, 24, 1, "MQBTUDRWFGHXJELINOPKSAVC"},
{24L, 24, 2, "IOQRBEUVFWGHKLAXMNPSCDTJ" "NJXOVGDKSMTFIPQELCURBWAH"},
{48L, 24, 2, "QUEJWVXFKLRIPGMNSACBOTDH" "HSNOPWLDTUVBRIAKXFGCQEMJ"},
{24L, 24, 2, "QXEJWPUMKLRIVBFTSACGHNDO" "TWHNXLRIOPUMSACQVBFDEJGK"},
{48L, 24, 2, "QUEJWVXFKLRIPGMNSACBOTDH" "BAFGHCDEMNOPIJKLTUVQRSXW"},
{48L, 24, 3,
"QXKJWVUMESRIPGFTLDCBONAH" "JUEQRPXFKLWCVBMNSAIGHTDO"
"HSNOPWLDTUVBRIAKXFGCQEMJ"},
{24L, 24, 3,
"QUKJWPXFESRIVBMNLDCGHTAO" "JXEQRVUMKLWCPGFTSAIBONDH"
"TRONXLWCHVUMSAIJPGFDEQBK"},
{16L, 24, 2, "MRGTULWIOPFXSDJQBVNEKCHA" "VKXHOQASNTPBCWDEUFGIJLMR"},
{16L, 24, 2, "MRGTULWIOPFXSDJQBVNEKCHA" "RMLWIGTUSDJQOPFXEKCBVNAH"},
{48L, 24, 2, "IULQRGXMSDCWOPNTEKJBVFAH" "GLMOPRSDTUBVWIEKFXHJQANC"},
{24L, 24, 2, "UJPXMRCSNHGTLWIKFVBEDQOA" "NRUFVLWIPXMOJEDQHGTCSABK"},
{24L, 24, 2, "MIBTUAQRFGHXCDEWNOPJKLVS" "OKXVFWSCGUTNDRQJBPMALIHE"},
{144L, 24, 3,
"QXKJWVUMESRIPGFTLDCBONAH" "JUEQRPXFKLWCVBMNSAIGHTDO"
"BAFGHCDEMNOPIJKLTUVQRSXW"},
{336L, 24, 3,
"QTKJWONXESRIHVUMLDCPGFAB" "JNEQRHTUKLWCOPXFSAIVBMDG"
"HENOPJKLTUVBQRSAXFGWCDMI"},
/* order 25 */
{20L, 25, 1, "EHILMNPQRSFTUVBJWXDOYGAKC"},
{480L, 25, 2, "EHILMNPQRSCTUVBFWXDJYGOKA" "BDEGHIKLMNAPQRSCTUVFWXJYO"},
/* order 26 */
{156L, 26, 2,
"EXGZIBKDMFOHQJSLUNWPYRATCV" "BADCFEHGJILKNMPORQTSVUXWZY"},
{12L, 26, 1, "FEHGJILKNMPORQTSVUXWZYBADC"},
};
static const struct groups groups[] = {
{0, NULL}, /* trivial case: 0 */
{0, NULL}, /* trivial case: 1 */
{1, groupdata + 0}, /* 2 */
{1, groupdata + 1}, /* 3 */
{2, groupdata + 2}, /* 4 */
{1, groupdata + 4}, /* 5 */
{2, groupdata + 5}, /* 6 */
{1, groupdata + 7}, /* 7 */
{5, groupdata + 8}, /* 8 */
{2, groupdata + 13}, /* 9 */
{2, groupdata + 15}, /* 10 */
{1, groupdata + 17}, /* 11 */
{5, groupdata + 18}, /* 12 */
{1, groupdata + 23}, /* 13 */
{2, groupdata + 24}, /* 14 */
{1, groupdata + 26}, /* 15 */
{14, groupdata + 27}, /* 16 */
{1, groupdata + 41}, /* 17 */
{5, groupdata + 42}, /* 18 */
{1, groupdata + 47}, /* 19 */
{5, groupdata + 48}, /* 20 */
{2, groupdata + 53}, /* 21 */
{2, groupdata + 55}, /* 22 */
{1, groupdata + 57}, /* 23 */
{15, groupdata + 58}, /* 24 */
{2, groupdata + 73}, /* 25 */
{2, groupdata + 75}, /* 26 */
};
/* ----- data generated by group.gap ends ----- */
static char *new_game_desc(const game_params *params, random_state *rs,
char **aux, bool interactive)
{
int w = params->w, a = w*w;
digit *grid, *soln, *soln2;
int *indices;
int i, j, k, qh, qt;
int diff = params->diff;
const struct group *group;
char *desc, *p;
/*
* Difficulty exceptions: some combinations of size and
* difficulty cannot be satisfied, because all puzzles of at
* most that difficulty are actually even easier.
*
* Remember to re-test this whenever a change is made to the
* solver logic!
*
* I tested it using the following shell command:
for d in t n h x u; do
for id in '' i; do
for i in {3..9}; do
echo -n "./group --generate 1 ${i}d${d}${id}: "
perl -e 'alarm 30; exec @ARGV' \
./group --generate 1 ${i}d${d}${id} >/dev/null && echo ok
done
done
done
* Of course, it's better to do that after taking the exceptions
* _out_, so as to detect exceptions that should be removed as
* well as those which should be added.
*/
if (w < 5 && diff == DIFF_UNREASONABLE)
diff--;
if ((w < 5 || ((w == 6 || w == 8) && params->id)) && diff == DIFF_EXTREME)
diff--;
if ((w < 6 || (w == 6 && params->id)) && diff == DIFF_HARD)
diff--;
if ((w < 4 || (w == 4 && params->id)) && diff == DIFF_NORMAL)
diff--;
grid = snewn(a, digit);
soln = snewn(a, digit);
soln2 = snewn(a, digit);
indices = snewn(a, int);
while (1) {
/*
* Construct a valid group table, by picking a group from
* the above data table, decompressing it into a full
* representation by BFS, and then randomly permuting its
* non-identity elements.
*
* We build the canonical table in 'soln' (and use 'grid' as
* our BFS queue), then transfer the table into 'grid'
* having shuffled the rows.
*/
assert(w >= 2);
assert(w < lenof(groups));
group = groups[w].groups + random_upto(rs, groups[w].ngroups);
assert(group->order == w);
memset(soln, 0, a);
for (i = 0; i < w; i++)
soln[i] = i+1;
qh = qt = 0;
grid[qt++] = 1;
while (qh < qt) {
digit *row, *newrow;
i = grid[qh++];
row = soln + (i-1)*w;
for (j = 0; j < group->ngens; j++) {
int nri;
const char *gen = group->gens + j*w;
/*
* Apply each group generator to row, constructing a
* new row.
*/
nri = gen[row[0]-1] - 'A' + 1; /* which row is it? */
newrow = soln + (nri-1)*w;
if (!newrow[0]) { /* not done yet */
for (k = 0; k < w; k++)
newrow[k] = gen[row[k]-1] - 'A' + 1;
grid[qt++] = nri;
}
}
}
/* That's got the canonical table. Now shuffle it. */
for (i = 0; i < w; i++)
soln2[i] = i;
if (params->id) /* do we shuffle in the identity? */
shuffle(soln2+1, w-1, sizeof(*soln2), rs);
else
shuffle(soln2, w, sizeof(*soln2), rs);
for (i = 0; i < w; i++)
for (j = 0; j < w; j++)
grid[(soln2[i])*w+(soln2[j])] = soln2[soln[i*w+j]-1]+1;
/*
* Remove entries one by one while the puzzle is still
* soluble at the appropriate difficulty level.
*/
memcpy(soln, grid, a);
if (!params->id) {
/*
* Start by blanking the entire identity row and column,
* and also another row and column so that the player
* can't trivially determine which element is the
* identity.
*/
j = 1 + random_upto(rs, w-1); /* pick a second row/col to blank */
for (i = 0; i < w; i++) {
grid[(soln2[0])*w+i] = grid[i*w+(soln2[0])] = 0;
grid[(soln2[j])*w+i] = grid[i*w+(soln2[j])] = 0;
}
memcpy(soln2, grid, a);
if (solver(params, soln2, diff) > diff)
continue; /* go round again if that didn't work */
}
k = 0;
for (i = (params->id ? 1 : 0); i < w; i++)
for (j = (params->id ? 1 : 0); j < w; j++)
if (grid[i*w+j])
indices[k++] = i*w+j;
shuffle(indices, k, sizeof(*indices), rs);
for (i = 0; i < k; i++) {
memcpy(soln2, grid, a);
soln2[indices[i]] = 0;
if (solver(params, soln2, diff) <= diff)
grid[indices[i]] = 0;
}
/*
* Make sure the puzzle isn't too easy.
*/
if (diff > 0) {
memcpy(soln2, grid, a);
if (solver(params, soln2, diff-1) < diff)
continue; /* go round and try again */
}
/*
* Done.
*/
break;
}
/*
* Encode the puzzle description.
*/
desc = snewn(a*20, char);
p = encode_grid(desc, grid, a);
*p++ = '\0';
desc = sresize(desc, p - desc, char);
/*
* Encode the solution.
*/
*aux = snewn(a+2, char);
(*aux)[0] = 'S';
for (i = 0; i < a; i++)
(*aux)[i+1] = TOCHAR(soln[i], params->id);
(*aux)[a+1] = '\0';
sfree(grid);
sfree(soln);
sfree(soln2);
sfree(indices);
return desc;
}
/* ----------------------------------------------------------------------
* Gameplay.
*/
static const char *validate_grid_desc(const char **pdesc, int range, int area)
{
const char *desc = *pdesc;
int squares = 0;
while (*desc && *desc != ',') {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
squares += n - 'a' + 1;
} else if (n == '_') {
/* do nothing */;
} else if (n > '0' && n <= '9') {
int val = atoi(desc-1);
if (val < 1 || val > range)
return "Out-of-range number in game description";
squares++;
while (*desc >= '0' && *desc <= '9')
desc++;
} else
return "Invalid character in game description";
}
if (squares < area)
return "Not enough data to fill grid";
if (squares > area)
return "Too much data to fit in grid";
*pdesc = desc;
return NULL;
}
static const char *validate_desc(const game_params *params, const char *desc)
{
int w = params->w, a = w*w;
const char *p = desc;
return validate_grid_desc(&p, w, a);
}
static const char *spec_to_grid(const char *desc, digit *grid, int area)
{
int i = 0;
while (*desc && *desc != ',') {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
int run = n - 'a' + 1;
assert(i + run <= area);
while (run-- > 0)
grid[i++] = 0;
} else if (n == '_') {
/* do nothing */;
} else if (n > '0' && n <= '9') {
assert(i < area);
grid[i++] = atoi(desc-1);
while (*desc >= '0' && *desc <= '9')
desc++;
} else {
assert(!"We can't get here");
}
}
assert(i == area);
return desc;
}
static game_state *new_game(midend *me, const game_params *params,
const char *desc)
{
int w = params->w, a = w*w;
game_state *state = snew(game_state);
int i;
state->par = *params; /* structure copy */
state->grid = snewn(a, digit);
state->common = snew(group_common);
state->common->refcount = 1;
state->common->immutable = snewn(a, bool);
state->pencil = snewn(a, int);
for (i = 0; i < a; i++) {
state->grid[i] = 0;
state->common->immutable[i] = false;
state->pencil[i] = 0;
}
state->sequence = snewn(w, digit);
state->dividers = snewn(w, int);
for (i = 0; i < w; i++) {
state->sequence[i] = i;
state->dividers[i] = -1;
}
desc = spec_to_grid(desc, state->grid, a);
for (i = 0; i < a; i++)
if (state->grid[i] != 0)
state->common->immutable[i] = true;
state->completed = false;
state->cheated = false;
return state;
}
static game_state *dup_game(const game_state *state)
{
int w = state->par.w, a = w*w;
game_state *ret = snew(game_state);
ret->par = state->par; /* structure copy */
ret->grid = snewn(a, digit);
ret->common = state->common;
ret->common->refcount++;
ret->pencil = snewn(a, int);
ret->sequence = snewn(w, digit);
ret->dividers = snewn(w, int);
memcpy(ret->grid, state->grid, a*sizeof(digit));
memcpy(ret->pencil, state->pencil, a*sizeof(int));
memcpy(ret->sequence, state->sequence, w*sizeof(digit));
memcpy(ret->dividers, state->dividers, w*sizeof(int));
ret->completed = state->completed;
ret->cheated = state->cheated;
return ret;
}
static void free_game(game_state *state)
{
sfree(state->grid);
if (--state->common->refcount == 0) {
sfree(state->common->immutable);
sfree(state->common);
}
sfree(state->pencil);
sfree(state->sequence);
sfree(state);
}
static char *solve_game(const game_state *state, const game_state *currstate,
const char *aux, const char **error)
{
int w = state->par.w, a = w*w;
int i, ret;
digit *soln;
char *out;
if (aux)
return dupstr(aux);
soln = snewn(a, digit);
memcpy(soln, state->grid, a*sizeof(digit));
ret = solver(&state->par, soln, DIFFCOUNT-1);
if (ret == diff_impossible) {
*error = "No solution exists for this puzzle";
out = NULL;
} else if (ret == diff_ambiguous) {
*error = "Multiple solutions exist for this puzzle";
out = NULL;
} else {
out = snewn(a+2, char);
out[0] = 'S';
for (i = 0; i < a; i++)
out[i+1] = TOCHAR(soln[i], state->par.id);
out[a+1] = '\0';
}
sfree(soln);
return out;
}
static bool game_can_format_as_text_now(const game_params *params)
{
return true;
}
static char *game_text_format(const game_state *state)
{
int w = state->par.w;
int x, y;
char *ret, *p, ch;
ret = snewn(2*w*w+1, char); /* leave room for terminating NUL */
p = ret;
for (y = 0; y < w; y++) {
for (x = 0; x < w; x++) {
digit d = state->grid[y*w+x];
if (d == 0) {
ch = '.';
} else {
ch = TOCHAR(d, state->par.id);
}
*p++ = ch;
if (x == w-1) {
*p++ = '\n';
} else {
*p++ = ' ';
}
}
}
assert(p - ret == 2*w*w);
*p = '\0';
return ret;
}
struct game_ui {
/*
* These are the coordinates of the primary highlighted square on
* the grid, if hshow = 1.
*/
int hx, hy;
/*
* These are the coordinates hx,hy _before_ they go through
* state->sequence.
*/
int ohx, ohy;
/*
* These variables give the length and displacement of a diagonal
* sequence of highlighted squares starting at ohx,ohy (still if
* hshow = 1). To find the squares' real coordinates, for 0<=i<dn,
* compute ohx+i*odx and ohy+i*ody and then map through
* state->sequence.
*/
int odx, ody, odn;
/*
* This indicates whether the current highlight is a
* pencil-mark one or a real one.
*/
bool hpencil;
/*
* This indicates whether or not we're showing the highlight
* (used to be hx = hy = -1); important so that when we're
* using the cursor keys it doesn't keep coming back at a
* fixed position. When hshow = 1, pressing a valid number
* or letter key or Space will enter that number or letter in the grid.
*/
bool hshow;
/*
* This indicates whether we're using the highlight as a cursor;
* it means that it doesn't vanish on a keypress, and that it is
* allowed on immutable squares.
*/
bool hcursor;
/*
* This indicates whether we're dragging a table header to
* reposition an entire row or column.
*/
int drag; /* 0=none 1=row 2=col */
int dragnum; /* element being dragged */
int dragpos; /* its current position */
int edgepos;
};
static game_ui *new_ui(const game_state *state)
{
game_ui *ui = snew(game_ui);
ui->hx = ui->hy = 0;
ui->hpencil = false;
ui->hshow = false;
ui->hcursor = false;
ui->drag = 0;
return ui;
}
static void free_ui(game_ui *ui)
{
sfree(ui);
}
static char *encode_ui(const game_ui *ui)
{
return NULL;
}
static void decode_ui(game_ui *ui, const char *encoding)
{
}
static void game_changed_state(game_ui *ui, const game_state *oldstate,
const game_state *newstate)
{
int w = newstate->par.w;
/*
* We prevent pencil-mode highlighting of a filled square, unless
* we're using the cursor keys. So if the user has just filled in
* a square which we had a pencil-mode highlight in (by Undo, or
* by Redo, or by Solve), then we cancel the highlight.
*/
if (ui->hshow && ui->hpencil && !ui->hcursor &&
newstate->grid[ui->hy * w + ui->hx] != 0) {
ui->hshow = false;
}
if (ui->hshow && ui->odn > 1) {
/*
* Reordering of rows or columns within the range of a
* multifill selection cancels the multifill and deselects
* everything.
*/
int i;
for (i = 0; i < ui->odn; i++) {
if (oldstate->sequence[ui->ohx + i*ui->odx] !=
newstate->sequence[ui->ohx + i*ui->odx]) {
ui->hshow = false;
break;
}
if (oldstate->sequence[ui->ohy + i*ui->ody] !=
newstate->sequence[ui->ohy + i*ui->ody]) {
ui->hshow = false;
break;
}
}
} else if (ui->hshow &&
(newstate->sequence[ui->ohx] != ui->hx ||
newstate->sequence[ui->ohy] != ui->hy)) {
/*
* Otherwise, reordering of the row or column containing the
* selection causes the selection to move with it.
*/
int i;
for (i = 0; i < w; i++) {
if (newstate->sequence[i] == ui->hx)
ui->ohx = i;
if (newstate->sequence[i] == ui->hy)
ui->ohy = i;
}
}
}
#define PREFERRED_TILESIZE 48
#define TILESIZE (ds->tilesize)
#define BORDER (TILESIZE / 2)
#define LEGEND (TILESIZE)
#define GRIDEXTRA max((TILESIZE / 32),1)
#define COORD(x) ((x)*TILESIZE + BORDER + LEGEND)
#define FROMCOORD(x) (((x)+(TILESIZE-BORDER-LEGEND)) / TILESIZE - 1)
#define FLASH_TIME 0.4F
#define DF_DIVIDER_TOP 0x1000
#define DF_DIVIDER_BOT 0x2000
#define DF_DIVIDER_LEFT 0x4000
#define DF_DIVIDER_RIGHT 0x8000
#define DF_HIGHLIGHT 0x0400
#define DF_HIGHLIGHT_PENCIL 0x0200
#define DF_IMMUTABLE 0x0100
#define DF_LEGEND 0x0080
#define DF_DIGIT_MASK 0x001F
#define EF_DIGIT_SHIFT 5
#define EF_DIGIT_MASK ((1 << EF_DIGIT_SHIFT) - 1)
#define EF_LEFT_SHIFT 0
#define EF_RIGHT_SHIFT (3*EF_DIGIT_SHIFT)
#define EF_LEFT_MASK ((1UL << (3*EF_DIGIT_SHIFT)) - 1UL)
#define EF_RIGHT_MASK (EF_LEFT_MASK << EF_RIGHT_SHIFT)
#define EF_LATIN (1UL << (6*EF_DIGIT_SHIFT))
struct game_drawstate {
game_params par;
int w, tilesize;
bool started;
long *tiles, *legend, *pencil, *errors;
long *errtmp;
digit *sequence;
};
static bool check_errors(const game_state *state, long *errors)
{
int w = state->par.w, a = w*w;
digit *grid = state->grid;
int i, j, k, x, y;
bool errs = false;
/*
* To verify that we have a valid group table, it suffices to
* test latin-square-hood and associativity only. All the other
* group axioms follow from those two.
*
* Proof:
*
* Associativity is given; closure is obvious from latin-
* square-hood. We need to show that an identity exists and that
* every element has an inverse.
*
* Identity: take any element a. There will be some element e
* such that ea=a (in a latin square, every element occurs in
* every row and column, so a must occur somewhere in the a
* column, say on row e). For any other element b, there must
* exist x such that ax=b (same argument from latin-square-hood
* again), and then associativity gives us eb = e(ax) = (ea)x =
* ax = b. Hence eb=b for all b, i.e. e is a left-identity. A
* similar argument tells us that there must be some f which is
* a right-identity, and then we show they are the same element
* by observing that ef must simultaneously equal e and equal f.
*
* Inverses: given any a, by the latin-square argument again,
* there must exist p and q such that pa=e and aq=e (i.e. left-
* and right-inverses). We can show these are equal by
* associativity: p = pe = p(aq) = (pa)q = eq = q. []
*/
if (errors)
for (i = 0; i < a; i++)
errors[i] = 0;
for (y = 0; y < w; y++) {
unsigned long mask = 0, errmask = 0;
for (x = 0; x < w; x++) {
unsigned long bit = 1UL << grid[y*w+x];
errmask |= (mask & bit);
mask |= bit;
}
if (mask != (1 << (w+1)) - (1 << 1)) {
errs = true;
errmask &= ~1UL;
if (errors) {
for (x = 0; x < w; x++)
if (errmask & (1UL << grid[y*w+x]))
errors[y*w+x] |= EF_LATIN;
}
}
}
for (x = 0; x < w; x++) {
unsigned long mask = 0, errmask = 0;
for (y = 0; y < w; y++) {
unsigned long bit = 1UL << grid[y*w+x];
errmask |= (mask & bit);
mask |= bit;
}
if (mask != (1 << (w+1)) - (1 << 1)) {
errs = true;
errmask &= ~1UL;
if (errors) {
for (y = 0; y < w; y++)
if (errmask & (1UL << grid[y*w+x]))
errors[y*w+x] |= EF_LATIN;
}
}
}
for (i = 1; i < w; i++)
for (j = 1; j < w; j++)
for (k = 1; k < w; k++)
if (grid[i*w+j] && grid[j*w+k] &&
grid[(grid[i*w+j]-1)*w+k] &&
grid[i*w+(grid[j*w+k]-1)] &&
grid[(grid[i*w+j]-1)*w+k] != grid[i*w+(grid[j*w+k]-1)]) {
if (errors) {
int a = i+1, b = j+1, c = k+1;
int ab = grid[i*w+j], bc = grid[j*w+k];
int left = (ab-1)*w+(c-1), right = (a-1)*w+(bc-1);
/*
* If the appropriate error slot is already
* used for one of the squares, we don't
* fill either of them.
*/
if (!(errors[left] & EF_LEFT_MASK) &&
!(errors[right] & EF_RIGHT_MASK)) {
long err;
err = a;
err = (err << EF_DIGIT_SHIFT) | b;
err = (err << EF_DIGIT_SHIFT) | c;
errors[left] |= err << EF_LEFT_SHIFT;
errors[right] |= err << EF_RIGHT_SHIFT;
}
}
errs = true;
}
return errs;
}
static int find_in_sequence(digit *seq, int len, digit n)
{
int i;
for (i = 0; i < len; i++)
if (seq[i] == n)
return i;
assert(!"Should never get here");
return -1;
}
static char *interpret_move(const game_state *state, game_ui *ui,
const game_drawstate *ds,
int x, int y, int button)
{
int w = state->par.w;
int tx, ty;
char buf[80];
button &= ~MOD_MASK;
tx = FROMCOORD(x);
ty = FROMCOORD(y);
if (ui->drag) {
if (IS_MOUSE_DRAG(button)) {
int tcoord = ((ui->drag &~ 4) == 1 ? ty : tx);
ui->drag |= 4; /* some movement has happened */
if (tcoord >= 0 && tcoord < w) {
ui->dragpos = tcoord;
return UI_UPDATE;
}
} else if (IS_MOUSE_RELEASE(button)) {
if (ui->drag & 4) {
ui->drag = 0; /* end drag */
if (state->sequence[ui->dragpos] == ui->dragnum)
return UI_UPDATE; /* drag was a no-op overall */
sprintf(buf, "D%d,%d", ui->dragnum, ui->dragpos);
return dupstr(buf);
} else {
ui->drag = 0; /* end 'drag' */
if (ui->edgepos > 0 && ui->edgepos < w) {
sprintf(buf, "V%d,%d",
state->sequence[ui->edgepos-1],
state->sequence[ui->edgepos]);
return dupstr(buf);
} else
return UI_UPDATE; /* no-op */
}
}
} else if (IS_MOUSE_DOWN(button)) {
if (tx >= 0 && tx < w && ty >= 0 && ty < w) {
int otx = tx, oty = ty;
tx = state->sequence[tx];
ty = state->sequence[ty];
if (button == LEFT_BUTTON) {
if (tx == ui->hx && ty == ui->hy &&
ui->hshow && !ui->hpencil) {
ui->hshow = false;
} else {
ui->hx = tx;
ui->hy = ty;
ui->ohx = otx;
ui->ohy = oty;
ui->odx = ui->ody = 0;
ui->odn = 1;
ui->hshow = !state->common->immutable[ty*w+tx];
ui->hpencil = false;
}
ui->hcursor = false;
return UI_UPDATE;
}
if (button == RIGHT_BUTTON) {
/*
* Pencil-mode highlighting for non filled squares.
*/
if (state->grid[ty*w+tx] == 0) {
if (tx == ui->hx && ty == ui->hy &&
ui->hshow && ui->hpencil) {
ui->hshow = false;
} else {
ui->hpencil = true;
ui->hx = tx;
ui->hy = ty;
ui->ohx = otx;
ui->ohy = oty;
ui->odx = ui->ody = 0;
ui->odn = 1;
ui->hshow = true;
}
} else {
ui->hshow = false;
}
ui->hcursor = false;
return UI_UPDATE;
}
} else if (tx >= 0 && tx < w && ty == -1) {
ui->drag = 2;
ui->dragnum = state->sequence[tx];
ui->dragpos = tx;
ui->edgepos = FROMCOORD(x + TILESIZE/2);
return UI_UPDATE;
} else if (ty >= 0 && ty < w && tx == -1) {
ui->drag = 1;
ui->dragnum = state->sequence[ty];
ui->dragpos = ty;
ui->edgepos = FROMCOORD(y + TILESIZE/2);
return UI_UPDATE;
}
} else if (IS_MOUSE_DRAG(button)) {
if (!ui->hpencil &&
tx >= 0 && tx < w && ty >= 0 && ty < w &&
abs(tx - ui->ohx) == abs(ty - ui->ohy)) {
ui->odn = abs(tx - ui->ohx) + 1;
ui->odx = (tx < ui->ohx ? -1 : +1);
ui->ody = (ty < ui->ohy ? -1 : +1);
} else {
ui->odx = ui->ody = 0;
ui->odn = 1;
}
return UI_UPDATE;
}
if (IS_CURSOR_MOVE(button)) {
int cx = find_in_sequence(state->sequence, w, ui->hx);
int cy = find_in_sequence(state->sequence, w, ui->hy);
move_cursor(button, &cx, &cy, w, w, false);
ui->hx = state->sequence[cx];
ui->hy = state->sequence[cy];
ui->hshow = true;
ui->hcursor = true;
return UI_UPDATE;
}
if (ui->hshow &&
(button == CURSOR_SELECT)) {
ui->hpencil = !ui->hpencil;
ui->hcursor = true;
return UI_UPDATE;
}
if (ui->hshow &&
((ISCHAR(button) && FROMCHAR(button, state->par.id) <= w) ||
button == CURSOR_SELECT2 || button == '\b')) {
int n = FROMCHAR(button, state->par.id);
int i, buflen;
char *movebuf;
if (button == CURSOR_SELECT2 || button == '\b')
n = 0;
for (i = 0; i < ui->odn; i++) {
int x = state->sequence[ui->ohx + i*ui->odx];
int y = state->sequence[ui->ohy + i*ui->ody];
int index = y*w+x;
/*
* Can't make pencil marks in a filled square. This can only
* become highlighted if we're using cursor keys.
*/
if (ui->hpencil && state->grid[index])
return NULL;
/*
* Can't do anything to an immutable square. Exception:
* trying to set it to what it already was is OK (so that
* multifilling can set a whole diagonal to a without
* having to detour round the one immutable square in the
* middle that already said a).
*/
if (!ui->hpencil && state->grid[index] == n)
/* OK even if it is immutable */;
else if (state->common->immutable[index])
return NULL;
}
movebuf = snewn(80 * ui->odn, char);
buflen = sprintf(movebuf, "%c%d,%d,%d",
(char)(ui->hpencil && n > 0 ? 'P' : 'R'),
ui->hx, ui->hy, n);
for (i = 1; i < ui->odn; i++) {
assert(buflen < i*80);
buflen += sprintf(movebuf + buflen, "+%d,%d",
state->sequence[ui->ohx + i*ui->odx],
state->sequence[ui->ohy + i*ui->ody]);
}
movebuf = sresize(movebuf, buflen+1, char);
if (!ui->hcursor) ui->hshow = false;
return movebuf;
}
if (button == 'M' || button == 'm')
return dupstr("M");
return NULL;
}
static game_state *execute_move(const game_state *from, const char *move)
{
int w = from->par.w, a = w*w;
game_state *ret;
int x, y, i, j, n, pos;
if (move[0] == 'S') {
ret = dup_game(from);
ret->completed = ret->cheated = true;
for (i = 0; i < a; i++) {
if (!ISCHAR(move[i+1]) || FROMCHAR(move[i+1], from->par.id) > w) {
free_game(ret);
return NULL;
}
ret->grid[i] = FROMCHAR(move[i+1], from->par.id);
ret->pencil[i] = 0;
}
if (move[a+1] != '\0') {
free_game(ret);
return NULL;
}
return ret;
} else if ((move[0] == 'P' || move[0] == 'R') &&
sscanf(move+1, "%d,%d,%d%n", &x, &y, &n, &pos) == 3 &&
n >= 0 && n <= w) {
const char *mp = move + 1 + pos;
bool pencil = (move[0] == 'P');
ret = dup_game(from);
while (1) {
if (x < 0 || x >= w || y < 0 || y >= w) {
free_game(ret);
return NULL;
}
if (from->common->immutable[y*w+x] &&
!(!pencil && from->grid[y*w+x] == n))
return NULL;
if (move[0] == 'P' && n > 0) {
ret->pencil[y*w+x] ^= 1 << n;
} else {
ret->grid[y*w+x] = n;
ret->pencil[y*w+x] = 0;
}
if (!*mp)
break;
if (*mp != '+')
return NULL;
if (sscanf(mp, "+%d,%d%n", &x, &y, &pos) < 2)
return NULL;
mp += pos;
}
if (!ret->completed && !check_errors(ret, NULL))
ret->completed = true;
return ret;
} else if (move[0] == 'M') {
/*
* Fill in absolutely all pencil marks everywhere. (I
* wouldn't use this for actual play, but it's a handy
* starting point when following through a set of
* diagnostics output by the standalone solver.)
*/
ret = dup_game(from);
for (i = 0; i < a; i++) {
if (!ret->grid[i])
ret->pencil[i] = (1 << (w+1)) - (1 << 1);
}
return ret;
} else if (move[0] == 'D' &&
sscanf(move+1, "%d,%d", &x, &y) == 2) {
/*
* Reorder the rows and columns so that digit x is in position
* y.
*/
ret = dup_game(from);
for (i = j = 0; i < w; i++) {
if (i == y) {
ret->sequence[i] = x;
} else {
if (from->sequence[j] == x)
j++;
ret->sequence[i] = from->sequence[j++];
}
}
/*
* Eliminate any obsoleted dividers.
*/
for (x = 0; x < w; x++) {
int i = ret->sequence[x];
int j = (x+1 < w ? ret->sequence[x+1] : -1);
if (ret->dividers[i] != j)
ret->dividers[i] = -1;
}
return ret;
} else if (move[0] == 'V' &&
sscanf(move+1, "%d,%d", &i, &j) == 2) {
ret = dup_game(from);
if (ret->dividers[i] == j)
ret->dividers[i] = -1;
else
ret->dividers[i] = j;
return ret;
} else
return NULL; /* couldn't parse move string */
}
/* ----------------------------------------------------------------------
* Drawing routines.
*/
#define SIZE(w) ((w) * TILESIZE + 2*BORDER + LEGEND)
static void game_compute_size(const 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 = *y = SIZE(params->w);
}
static void game_set_size(drawing *dr, game_drawstate *ds,
const game_params *params, int tilesize)
{
ds->tilesize = tilesize;
}
static float *game_colours(frontend *fe, int *ncolours)
{
float *ret = snewn(3 * NCOLOURS, float);
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
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 + 0] = 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] = 0.78F * 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;
ret[COL_ERROR * 3 + 2] = 0.0F;
ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2];
ret[COL_DIAGONAL * 3 + 0] = 0.95F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_DIAGONAL * 3 + 1] = 0.95F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_DIAGONAL * 3 + 2] = 0.95F * ret[COL_BACKGROUND * 3 + 2];
*ncolours = NCOLOURS;
return ret;
}
static game_drawstate *game_new_drawstate(drawing *dr, const game_state *state)
{
int w = state->par.w, a = w*w;
struct game_drawstate *ds = snew(struct game_drawstate);
int i;
ds->w = w;
ds->par = state->par; /* structure copy */
ds->tilesize = 0;
ds->started = false;
ds->tiles = snewn(a, long);
ds->legend = snewn(w, long);
ds->pencil = snewn(a, long);
ds->errors = snewn(a, long);
ds->sequence = snewn(a, digit);
for (i = 0; i < a; i++)
ds->tiles[i] = ds->pencil[i] = -1;
for (i = 0; i < w; i++)
ds->legend[i] = -1;
ds->errtmp = snewn(a, long);
return ds;
}
static void game_free_drawstate(drawing *dr, game_drawstate *ds)
{
sfree(ds->tiles);
sfree(ds->pencil);
sfree(ds->errors);
sfree(ds->errtmp);
sfree(ds->sequence);
sfree(ds);
}
static void draw_tile(drawing *dr, game_drawstate *ds, int x, int y, long tile,
long pencil, long error)
{
int w = ds->w /* , a = w*w */;
int tx, ty, tw, th;
int cx, cy, cw, ch;
char str[64];
tx = BORDER + LEGEND + x * TILESIZE + 1;
ty = BORDER + LEGEND + y * TILESIZE + 1;
cx = tx;
cy = ty;
cw = tw = TILESIZE-1;
ch = th = TILESIZE-1;
if (tile & DF_LEGEND) {
cx += TILESIZE/10;
cy += TILESIZE/10;
cw -= TILESIZE/5;
ch -= TILESIZE/5;
tile |= DF_IMMUTABLE;
}
clip(dr, cx, cy, cw, ch);
/* background needs erasing */
draw_rect(dr, cx, cy, cw, ch,
(tile & DF_HIGHLIGHT) ? COL_HIGHLIGHT :
(x == y) ? COL_DIAGONAL : COL_BACKGROUND);
/* dividers */
if (tile & DF_DIVIDER_TOP)
draw_rect(dr, cx, cy, cw, 1, COL_GRID);
if (tile & DF_DIVIDER_BOT)
draw_rect(dr, cx, cy+ch-1, cw, 1, COL_GRID);
if (tile & DF_DIVIDER_LEFT)
draw_rect(dr, cx, cy, 1, ch, COL_GRID);
if (tile & DF_DIVIDER_RIGHT)
draw_rect(dr, cx+cw-1, cy, 1, ch, COL_GRID);
/* pencil-mode highlight */
if (tile & DF_HIGHLIGHT_PENCIL) {
int coords[6];
coords[0] = cx;
coords[1] = cy;
coords[2] = cx+cw/2;
coords[3] = cy;
coords[4] = cx;
coords[5] = cy+ch/2;
draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT);
}
/* new number needs drawing? */
if (tile & DF_DIGIT_MASK) {
str[1] = '\0';
str[0] = TOCHAR(tile & DF_DIGIT_MASK, ds->par.id);
draw_text(dr, tx + TILESIZE/2, ty + TILESIZE/2,
FONT_VARIABLE, TILESIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE,
(error & EF_LATIN) ? COL_ERROR :
(tile & DF_IMMUTABLE) ? COL_GRID : COL_USER, str);
if (error & EF_LEFT_MASK) {
int a = (error >> (EF_LEFT_SHIFT+2*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
int b = (error >> (EF_LEFT_SHIFT+1*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
int c = (error >> (EF_LEFT_SHIFT ))&EF_DIGIT_MASK;
char buf[10];
sprintf(buf, "(%c%c)%c", TOCHAR(a, ds->par.id),
TOCHAR(b, ds->par.id), TOCHAR(c, ds->par.id));
draw_text(dr, tx + TILESIZE/2, ty + TILESIZE/6,
FONT_VARIABLE, TILESIZE/6, ALIGN_VCENTRE | ALIGN_HCENTRE,
COL_ERROR, buf);
}
if (error & EF_RIGHT_MASK) {
int a = (error >> (EF_RIGHT_SHIFT+2*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
int b = (error >> (EF_RIGHT_SHIFT+1*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
int c = (error >> (EF_RIGHT_SHIFT ))&EF_DIGIT_MASK;
char buf[10];
sprintf(buf, "%c(%c%c)", TOCHAR(a, ds->par.id),
TOCHAR(b, ds->par.id), TOCHAR(c, ds->par.id));
draw_text(dr, tx + TILESIZE/2, ty + TILESIZE - TILESIZE/6,
FONT_VARIABLE, TILESIZE/6, ALIGN_VCENTRE | ALIGN_HCENTRE,
COL_ERROR, buf);
}
} else {
int i, j, npencil;
int pl, pr, pt, pb;
float bestsize;
int pw, ph, minph, pbest, fontsize;
/* Count the pencil marks required. */
for (i = 1, npencil = 0; i <= w; i++)
if (pencil & (1 << i))
npencil++;
if (npencil) {
minph = 2;
/*
* Determine the bounding rectangle within which we're going
* to put the pencil marks.
*/
/* Start with the whole square */
pl = tx + GRIDEXTRA;
pr = pl + TILESIZE - GRIDEXTRA;
pt = ty + GRIDEXTRA;
pb = pt + TILESIZE - GRIDEXTRA;
/*
* We arrange our pencil marks in a grid layout, with
* the number of rows and columns adjusted to allow the
* maximum font size.
*
* So now we work out what the grid size ought to be.
*/
bestsize = 0.0;
pbest = 0;
/* Minimum */
for (pw = 3; pw < max(npencil,4); pw++) {
float fw, fh, fs;
ph = (npencil + pw - 1) / pw;
ph = max(ph, minph);
fw = (pr - pl) / (float)pw;
fh = (pb - pt) / (float)ph;
fs = min(fw, fh);
if (fs > bestsize) {
bestsize = fs;
pbest = pw;
}
}
assert(pbest > 0);
pw = pbest;
ph = (npencil + pw - 1) / pw;
ph = max(ph, minph);
/*
* Now we've got our grid dimensions, work out the pixel
* size of a grid element, and round it to the nearest
* pixel. (We don't want rounding errors to make the
* grid look uneven at low pixel sizes.)
*/
fontsize = min((pr - pl) / pw, (pb - pt) / ph);
/*
* Centre the resulting figure in the square.
*/
pl = tx + (TILESIZE - fontsize * pw) / 2;
pt = ty + (TILESIZE - fontsize * ph) / 2;
/*
* Now actually draw the pencil marks.
*/
for (i = 1, j = 0; i <= w; i++)
if (pencil & (1 << i)) {
int dx = j % pw, dy = j / pw;
str[1] = '\0';
str[0] = TOCHAR(i, ds->par.id);
draw_text(dr, pl + fontsize * (2*dx+1) / 2,
pt + fontsize * (2*dy+1) / 2,
FONT_VARIABLE, fontsize,
ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str);
j++;
}
}
}
unclip(dr);
draw_update(dr, cx, cy, cw, ch);
}
static void game_redraw(drawing *dr, game_drawstate *ds,
const game_state *oldstate, const game_state *state,
int dir, const game_ui *ui,
float animtime, float flashtime)
{
int w = state->par.w /*, a = w*w */;
int x, y, i, j;
if (!ds->started) {
/*
* The initial contents of the window are not guaranteed and
* can vary with front ends. To be on the safe side, all
* games should start by drawing a big background-colour
* rectangle covering the whole window.
*/
draw_rect(dr, 0, 0, SIZE(w), SIZE(w), COL_BACKGROUND);
/*
* Big containing rectangle.
*/
draw_rect(dr, COORD(0) - GRIDEXTRA, COORD(0) - GRIDEXTRA,
w*TILESIZE+1+GRIDEXTRA*2, w*TILESIZE+1+GRIDEXTRA*2,
COL_GRID);
draw_update(dr, 0, 0, SIZE(w), SIZE(w));
ds->started = true;
}
check_errors(state, ds->errtmp);
/*
* Construct a modified version of state->sequence which takes
* into account an unfinished drag operation.
*/
if (ui->drag) {
x = ui->dragnum;
y = ui->dragpos;
} else {
x = y = -1;
}
for (i = j = 0; i < w; i++) {
if (i == y) {
ds->sequence[i] = x;
} else {
if (state->sequence[j] == x)
j++;
ds->sequence[i] = state->sequence[j++];
}
}
/*
* Draw the table legend.
*/
for (x = 0; x < w; x++) {
int sx = ds->sequence[x];
long tile = (sx+1) | DF_LEGEND;
if (ds->legend[x] != tile) {
ds->legend[x] = tile;
draw_tile(dr, ds, -1, x, tile, 0, 0);
draw_tile(dr, ds, x, -1, tile, 0, 0);
}
}
for (y = 0; y < w; y++) {
int sy = ds->sequence[y];
for (x = 0; x < w; x++) {
long tile = 0L, pencil = 0L, error;
int sx = ds->sequence[x];
if (state->grid[sy*w+sx])
tile = state->grid[sy*w+sx];
else
pencil = (long)state->pencil[sy*w+sx];
if (state->common->immutable[sy*w+sx])
tile |= DF_IMMUTABLE;
if ((ui->drag == 5 && ui->dragnum == sy) ||
(ui->drag == 6 && ui->dragnum == sx)) {
tile |= DF_HIGHLIGHT;
} else if (ui->hshow) {
int i = abs(x - ui->ohx);
bool highlight = false;
if (ui->odn > 1) {
/*
* When a diagonal multifill selection is shown,
* we show it in its original grid position
* regardless of in-progress row/col drags. Moving
* every square about would be horrible.
*/
if (i >= 0 && i < ui->odn &&
x == ui->ohx + i*ui->odx &&
y == ui->ohy + i*ui->ody)
highlight = true;
} else {
/*
* For a single square, we move its highlight
* around with the drag.
*/
highlight = (ui->hx == sx && ui->hy == sy);
}
if (highlight)
tile |= (ui->hpencil ? DF_HIGHLIGHT_PENCIL : DF_HIGHLIGHT);
}
if (flashtime > 0 &&
(flashtime <= FLASH_TIME/3 ||
flashtime >= FLASH_TIME*2/3))
tile |= DF_HIGHLIGHT; /* completion flash */
if (y <= 0 || state->dividers[ds->sequence[y-1]] == sy)
tile |= DF_DIVIDER_TOP;
if (y+1 >= w || state->dividers[sy] == ds->sequence[y+1])
tile |= DF_DIVIDER_BOT;
if (x <= 0 || state->dividers[ds->sequence[x-1]] == sx)
tile |= DF_DIVIDER_LEFT;
if (x+1 >= w || state->dividers[sx] == ds->sequence[x+1])
tile |= DF_DIVIDER_RIGHT;
error = ds->errtmp[sy*w+sx];
if (ds->tiles[y*w+x] != tile ||
ds->pencil[y*w+x] != pencil ||
ds->errors[y*w+x] != error) {
ds->tiles[y*w+x] = tile;
ds->pencil[y*w+x] = pencil;
ds->errors[y*w+x] = error;
draw_tile(dr, ds, x, y, tile, pencil, error);
}
}
}
}
static float game_anim_length(const game_state *oldstate,
const game_state *newstate, int dir, game_ui *ui)
{
return 0.0F;
}
static float game_flash_length(const game_state *oldstate,
const game_state *newstate, int dir, game_ui *ui)
{
if (!oldstate->completed && newstate->completed &&
!oldstate->cheated && !newstate->cheated)
return FLASH_TIME;
return 0.0F;
}
static int game_status(const game_state *state)
{
return state->completed ? +1 : 0;
}
static bool game_timing_state(const game_state *state, game_ui *ui)
{
if (state->completed)
return false;
return true;
}
static void game_print_size(const game_params *params, float *x, float *y)
{
int pw, ph;
/*
* We use 9mm squares by default, like Solo.
*/
game_compute_size(params, 900, &pw, &ph);
*x = pw / 100.0F;
*y = ph / 100.0F;
}
static void game_print(drawing *dr, const game_state *state, int tilesize)
{
int w = state->par.w;
int ink = print_mono_colour(dr, 0);
int x, y;
/* Ick: fake up `ds->tilesize' for macro expansion purposes */
game_drawstate ads, *ds = &ads;
game_set_size(dr, ds, NULL, tilesize);
/*
* Border.
*/
print_line_width(dr, 3 * TILESIZE / 40);
draw_rect_outline(dr, BORDER + LEGEND, BORDER + LEGEND,
w*TILESIZE, w*TILESIZE, ink);
/*
* Legend on table.
*/
for (x = 0; x < w; x++) {
char str[2];
str[1] = '\0';
str[0] = TOCHAR(x+1, state->par.id);
draw_text(dr, BORDER+LEGEND + x*TILESIZE + TILESIZE/2,
BORDER + TILESIZE/2,
FONT_VARIABLE, TILESIZE/2,
ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str);
draw_text(dr, BORDER + TILESIZE/2,
BORDER+LEGEND + x*TILESIZE + TILESIZE/2,
FONT_VARIABLE, TILESIZE/2,
ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str);
}
/*
* Main grid.
*/
for (x = 1; x < w; x++) {
print_line_width(dr, TILESIZE / 40);
draw_line(dr, BORDER+LEGEND+x*TILESIZE, BORDER+LEGEND,
BORDER+LEGEND+x*TILESIZE, BORDER+LEGEND+w*TILESIZE, ink);
}
for (y = 1; y < w; y++) {
print_line_width(dr, TILESIZE / 40);
draw_line(dr, BORDER+LEGEND, BORDER+LEGEND+y*TILESIZE,
BORDER+LEGEND+w*TILESIZE, BORDER+LEGEND+y*TILESIZE, ink);
}
/*
* Numbers.
*/
for (y = 0; y < w; y++)
for (x = 0; x < w; x++)
if (state->grid[y*w+x]) {
char str[2];
str[1] = '\0';
str[0] = TOCHAR(state->grid[y*w+x], state->par.id);
draw_text(dr, BORDER+LEGEND + x*TILESIZE + TILESIZE/2,
BORDER+LEGEND + y*TILESIZE + TILESIZE/2,
FONT_VARIABLE, TILESIZE/2,
ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str);
}
}
#ifdef COMBINED
#define thegame group
#endif
const struct game thegame = {
"Group", NULL, NULL,
default_params,
game_fetch_preset, NULL,
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,
NULL, /* game_request_keys */
game_changed_state,
interpret_move,
execute_move,
PREFERRED_TILESIZE, game_compute_size, game_set_size,
game_colours,
game_new_drawstate,
game_free_drawstate,
game_redraw,
game_anim_length,
game_flash_length,
game_status,
true, false, game_print_size, game_print,
false, /* wants_statusbar */
false, game_timing_state,
REQUIRE_RBUTTON | REQUIRE_NUMPAD, /* flags */
};
#ifdef STANDALONE_SOLVER
#include <stdarg.h>
int main(int argc, char **argv)
{
game_params *p;
game_state *s;
char *id = NULL, *desc;
const char *err;
digit *grid;
bool grade = false;
int ret, diff;
bool really_show_working = false;
while (--argc > 0) {
char *p = *++argv;
if (!strcmp(p, "-v")) {
really_show_working = 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);
grid = snewn(p->w * p->w, digit);
/*
* When solving a Normal 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 */
solver_show_working = 0;
for (diff = 0; diff < DIFFCOUNT; diff++) {
memcpy(grid, s->grid, p->w * p->w);
ret = solver(&s->par, grid, diff);
if (ret <= diff)
break;
}
if (diff == DIFFCOUNT) {
if (grade)
printf("Difficulty rating: ambiguous\n");
else
printf("Unable to find a unique solution\n");
} else {
if (grade) {
if (ret == diff_impossible)
printf("Difficulty rating: impossible (no solution exists)\n");
else
printf("Difficulty rating: %s\n", group_diffnames[ret]);
} else {
solver_show_working = really_show_working;
memcpy(grid, s->grid, p->w * p->w);
ret = solver(&s->par, grid, diff);
if (ret != diff)
printf("Puzzle is inconsistent\n");
else {
memcpy(s->grid, grid, p->w * p->w);
fputs(game_text_format(s), stdout);
}
}
}
return 0;
}
#endif
/* vim: set shiftwidth=4 tabstop=8: */