ref: 9d9e02f1d5d5de569ec727ed98834c5f2426c515
parent: 86ee29ac4839870139d73b10be739fb6fcb93ef5
author: Simon Tatham <[email protected]>
date: Thu Feb 22 13:09:51 EST 2007
We may reluctantly permit the returning of a too-easy puzzle if an adequately hard one couldn't be found, but we must never return a puzzle harder than the user asked for, and we _certainly_ mustn't return one that we aren't even sure has a unique solution. However, when I attempted to implement this rule, it turned out that an attempt to generate a 15x15 Easy puzzle didn't terminate before I got bored and killed it. I'm therefore retiring the Easy difficulty level on the grounds that it's not a wide enough band to be useful. I've renamed Hard to Normal, and (while I was there) renamed Recursive to Unreasonable in line with my normal practice. [originally from svn r7309]
--- a/galaxies.c
+++ b/galaxies.c
@@ -66,9 +66,8 @@
};
#define DIFFLIST(A) \
- A(EASY,Easy,e) \
- A(HARD,Hard,h) \
- A(RECURSIVE,Recursive,r)
+ A(NORMAL,Normal,n) \
+ A(UNREASONABLE,Unreasonable,u)
#define ENUM(upper,title,lower) DIFF_ ## upper,
#define TITLE(upper,title,lower) #title,
@@ -135,16 +134,13 @@
/* make up some sensible default sizes */
-#define DEFAULT_PRESET 1
+#define DEFAULT_PRESET 0
static const game_params galaxies_presets[] = {- { 7, 7, DIFF_EASY },- { 7, 7, DIFF_HARD },- { 7, 7, DIFF_RECURSIVE },- { 10, 10, DIFF_EASY },- { 10, 10, DIFF_HARD },- { 15, 15, DIFF_EASY },- { 15, 15, DIFF_HARD },+ { 7, 7, DIFF_NORMAL },+ { 7, 7, DIFF_UNREASONABLE },+ { 10, 10, DIFF_NORMAL },+ { 15, 15, DIFF_NORMAL },};
static int game_fetch_preset(int i, char **name, game_params **params)
@@ -188,7 +184,7 @@
static void decode_params(game_params *params, char const *string)
{params->h = params->w = atoi(string);
- params->diff = DIFF_EASY;
+ params->diff = DIFF_NORMAL;
while (*string && isdigit((unsigned char)*string)) string++;
if (*string == 'x') {string++;
@@ -198,7 +194,7 @@
if (*string == 'd') {int i;
string++;
- for (i = 0; i <= DIFF_RECURSIVE; i++)
+ for (i = 0; i <= DIFF_UNREASONABLE; i++)
if (*string == galaxies_diffchars[i])
params->diff = i;
if (*string) string++;
@@ -266,7 +262,7 @@
* and custom_params will never generate anything that isn't
* within range.
*/
- assert(params->diff <= DIFF_RECURSIVE);
+ assert(params->diff <= DIFF_UNREASONABLE);
return NULL;
}
@@ -1242,7 +1238,13 @@
assert(diff != DIFF_IMPOSSIBLE);
if (diff != params->diff) {- if (ntries < MAXTRIES) goto generate;
+ /*
+ * We'll grudgingly accept a too-easy puzzle, but we must
+ * _not_ permit a too-hard one (one which the solver
+ * couldn't handle at all).
+ */
+ if (diff > params->diff ||
+ ntries < MAXTRIES) goto generate;
}
desc = encode_game(state);
@@ -1915,7 +1917,7 @@
else {/* precisely one solution */
if (diff == DIFF_IMPOSSIBLE)
- diff = DIFF_RECURSIVE;
+ diff = DIFF_UNREASONABLE;
else
diff = DIFF_AMBIGUOUS;
}
@@ -1941,7 +1943,7 @@
static int solver_state(game_state *state, int maxdiff)
{solver_ctx *sctx = new_solver(state);
- int ret, diff = DIFF_EASY;
+ int ret, diff = DIFF_NORMAL;
ret = solver_obvious(state);
if (ret < 0) {@@ -1958,21 +1960,16 @@
cont:
ret = foreach_edge(state, solver_lines_opposite_cb,
IMPOSSIBLE_QUITS, sctx);
- CHECKRET(DIFF_EASY);
+ CHECKRET(DIFF_NORMAL);
ret = foreach_tile(state, solver_spaces_oneposs_cb,
IMPOSSIBLE_QUITS, sctx);
- CHECKRET(DIFF_EASY);
+ CHECKRET(DIFF_NORMAL);
- /* more easy stuff? */
-
- if (maxdiff <= DIFF_EASY)
- break;
-
ret = solver_expand_dots(state, sctx);
- CHECKRET(DIFF_HARD);
+ CHECKRET(DIFF_NORMAL);
- if (maxdiff <= DIFF_HARD)
+ if (maxdiff <= DIFF_NORMAL)
break;
/* harder still? */
@@ -1983,7 +1980,7 @@
if (check_complete(state, 0)) goto got_result;
- diff = (maxdiff >= DIFF_RECURSIVE) ?
+ diff = (maxdiff >= DIFF_UNREASONABLE) ?
solver_recurse(state, maxdiff) : DIFF_UNFINISHED;
got_result:
@@ -2006,7 +2003,7 @@
int diff;
tosolve = dup_game(currstate);
- diff = solver_state(tosolve, DIFF_RECURSIVE);
+ diff = solver_state(tosolve, DIFF_UNREASONABLE);
if (diff != DIFF_UNFINISHED && diff != DIFF_IMPOSSIBLE) { debug(("solve_game solved with current state.\n"));goto solved;
@@ -2014,7 +2011,7 @@
free_game(tosolve);
tosolve = dup_game(state);
- diff = solver_state(tosolve, DIFF_RECURSIVE);
+ diff = solver_state(tosolve, DIFF_UNREASONABLE);
if (diff != DIFF_UNFINISHED && diff != DIFF_IMPOSSIBLE) { debug(("solve_game solved with original state.\n"));goto solved;
@@ -2163,7 +2160,7 @@
if (button == 'S' || button == 's') {char *ret;
game_state *tmp = dup_game(state);
- state->cdiff = solver_state(tmp, DIFF_RECURSIVE-1);
+ state->cdiff = solver_state(tmp, DIFF_UNREASONABLE-1);
ret = diff_game(state, tmp, 0);
free_game(tmp);
return ret;
@@ -2207,7 +2204,7 @@
if (button == 'H' || button == 'h')
solver_obvious(tmp);
else
- solver_state(tmp, DIFF_RECURSIVE-1);
+ solver_state(tmp, DIFF_UNREASONABLE-1);
ret = diff_game(state, tmp, 0);
free_game(tmp);
return ret;
@@ -3277,7 +3274,7 @@
state = new_game(NULL, p, desc);
dump_state(state);
- diff = solver_state(state, DIFF_RECURSIVE);
+ diff = solver_state(state, DIFF_UNREASONABLE);
printf("Generated %s game %dx%d:%s\n",galaxies_diffnames[diff], p->w, p->h, desc);
dump_state(state);
@@ -3378,7 +3375,7 @@
while (1) {p->w = random_upto(rs, 15) + 3;
p->h = random_upto(rs, 15) + 3;
- p->diff = random_upto(rs, DIFF_RECURSIVE);
+ p->diff = random_upto(rs, DIFF_UNREASONABLE);
diff = gen(p, rs, 0);
}
return 0;
@@ -3400,7 +3397,7 @@
exit(1);
}
s = new_game(NULL, p, desc);
- diff = solver_state(s, DIFF_RECURSIVE);
+ diff = solver_state(s, DIFF_UNREASONABLE);
dump_state(s);
printf("Puzzle is %s.\n", galaxies_diffnames[diff]);free_game(s);