ref: ef5c017a5f6863b5f8f2085b0c26106765d73ffb
parent: cd67072556c6b5934005b1777a465aca1e9df545
author: Jonas Kölker <jonaskoelker@yahoo.com>
date: Thu Oct 1 18:53:53 EDT 2015
Add hinting feature to Guess. Pressing H now suggests the lexicographically first row consistent with all previous feedback. The previous function of the H key to toggle a hold marker on the current peg is now performed by Space / CURSOR_SELECT2, which is more in line with other puzzles anyway.
--- a/guess.c
+++ b/guess.c
@@ -421,6 +421,7 @@
int drag_opeg; /* peg index, if dragged from a peg (from current guess), otherwise -1 */
int show_labels; /* label the colours with letters */
+ pegrow hint;
};
static game_ui *new_ui(const game_state *state)
@@ -437,6 +438,8 @@
static void free_ui(game_ui *ui)
{+ if (ui->hint)
+ free_pegrow(ui->hint);
free_pegrow(ui->curr_pegs);
sfree(ui->holds);
sfree(ui);
@@ -487,6 +490,11 @@
{int i;
+ if (newstate->next_go < oldstate->next_go) {+ sfree(ui->hint);
+ ui->hint = NULL;
+ }
+
/* Implement holds, clear other pegs.
* This does something that is arguably the Right Thing even
* for undo. */
@@ -571,7 +579,7 @@
ui->markable = is_markable(params, ui->curr_pegs);
}
-static int mark_pegs(pegrow guess, pegrow solution, int ncols)
+static int mark_pegs(pegrow guess, const pegrow solution, int ncols)
{int nc_place = 0, nc_colour = 0, i, j;
@@ -633,6 +641,125 @@
return buf;
}
+static void compute_hint(const game_state *state, game_ui *ui)
+{+ /* Suggest the lexicographically first row consistent with all
+ * previous feedback. This is not only a useful hint, but also
+ * a reasonable strategy if applied consistently. If the user
+ * uses hints in every turn, they may be able to intuit this
+ * strategy, or one similar to it. I (Jonas Kölker) came up
+ * with something close to it without seeing it in action. */
+
+ /* Some performance characteristics: I want to ask for each n,
+ * how many solutions are guessed in exactly n guesses if you
+ * use the hint in each turn.
+ *
+ * With 4 pegs and 6 colours you get the following histogram:
+ *
+ * 1 guesses: 1 solution
+ * 2 guesses: 4 solutions
+ * 3 guesses: 25 solutions
+ * 4 guesses: 108 solutions
+ * 5 guesses: 305 solutions
+ * 6 guesses: 602 solutions
+ * 7 guesses: 196 solutions
+ * 8 guesses: 49 solutions
+ * 9 guesses: 6 solutions
+ * (note: the tenth guess is never necessary.)
+ *
+ * With 5 pegs and 8 colours you get the following histogram:
+ *
+ * 1 guesses: 1 solution
+ * 2 guesses: 5 solutions
+ * 3 guesses: 43 solutions
+ * 4 guesses: 278 solutions
+ * 5 guesses: 1240 solutions
+ * 6 guesses: 3515 solutions
+ * 7 guesses: 7564 solutions
+ * 8 guesses: 14086 solutions
+ * 9 guesses: 4614 solutions
+ * 10 guesses: 1239 solutions
+ * 11 guesses: 175 solutions
+ * 12 guesses: 7 solutions
+ * 13 guesses: 1 solution
+ *
+ * The solution which takes too many guesses is {8, 8, 5, 6, 7}.+ * The game ID is c8p5g12Bm:4991e5e41a. */
+
+ int mincolour = 1, maxcolour = 0, i, j;
+
+ /* For large values of npegs and ncolours, the lexicographically
+ * next guess make take a while to find. Finding upper and
+ * lower limits on which colours we have to consider will speed
+ * this up, as will caching our progress from one invocation to
+ * the next. The latter strategy works, since if we have ruled
+ * out a candidate we will never reverse this judgment in the
+ * light of new information. Removing information, i.e. undo,
+ * will require us to backtrack somehow. We backtrack by fully
+ * forgetting our progress (and recomputing it if required). */
+
+ for (i = 0; i < state->next_go; ++i)
+ for (j = 0; j < state->params.npegs; ++j)
+ if (state->guesses[i]->pegs[j] > maxcolour)
+ maxcolour = state->guesses[i]->pegs[j];
+ maxcolour = min(maxcolour + 1, state->params.ncolours);
+
+increase_mincolour:
+ for (i = 0; i < state->next_go; ++i) {+ if (state->guesses[i]->feedback[0])
+ goto next_iteration;
+ for (j = 0; j < state->params.npegs; ++j)
+ if (state->guesses[i]->pegs[j] != mincolour)
+ goto next_iteration;
+ ++mincolour;
+ goto increase_mincolour;
+ next_iteration:
+ ;
+ }
+
+ if (!ui->hint) {+ ui->hint = new_pegrow(state->params.npegs);
+ for (i = 0; i < state->params.npegs; ++i)
+ ui->hint->pegs[i] = 1;
+ }
+
+ while (ui->hint->pegs[0] <= state->params.ncolours) {+ for (i = 0; i < state->next_go; ++i) {+ mark_pegs(ui->hint, state->guesses[i], maxcolour);
+ for (j = 0; j < state->params.npegs; ++j)
+ if (ui->hint->feedback[j] != state->guesses[i]->feedback[j])
+ goto increment_pegrow;
+ }
+ /* a valid guess was found; install it and return */
+ for (i = 0; i < state->params.npegs; ++i)
+ ui->curr_pegs->pegs[i] = ui->hint->pegs[i];
+
+ ui->markable = TRUE;
+ ui->peg_cur = state->params.npegs;
+ ui->display_cur = 1;
+ return;
+
+ increment_pegrow:
+ for (i = ui->hint->npegs;
+ ++ui->hint->pegs[--i], i && ui->hint->pegs[i] > maxcolour;
+ ui->hint->pegs[i] = mincolour);
+ }
+ /* No solution is compatible with the given hints. Impossible! */
+ /* (hack new_game_desc to create invalid solutions to get here) */
+
+ /* For some values of npegs and ncolours, the hinting function takes a
+ * long time to complete. To visually indicate completion with failure,
+ * should it ever happen, update the ui in some trivial way. This gives
+ * the user a sense of broken(ish)ness and futility. */
+ if (!ui->display_cur) {+ ui->display_cur = 1;
+ } else if (state->params.npegs == 1) {+ ui->display_cur = 0;
+ } else {+ ui->peg_cur = (ui->peg_cur + 1) % state->params.npegs;
+ }
+}
+
static char *interpret_move(const game_state *from, game_ui *ui,
const game_drawstate *ds,
int x, int y, int button)
@@ -754,6 +881,9 @@
if (button == CURSOR_UP && ui->colour_cur > 0)
ui->colour_cur--;
ret = "";
+ } else if (button == 'h' || button == 'H' || button == '?') {+ compute_hint(from, ui);
+ ret = "";
} else if (button == CURSOR_LEFT || button == CURSOR_RIGHT) {int maxcur = from->params.npegs;
if (ui->markable) maxcur++;
@@ -776,7 +906,7 @@
ui->display_cur = 1;
set_peg(&from->params, ui, ui->peg_cur, 0);
ret = "";
- } else if (button == 'H' || button == 'h') {+ } else if (button == CURSOR_SELECT2) {if (ui->peg_cur == from->params.npegs)
return NULL;
ui->display_cur = 1;
--- a/puzzles.but
+++ b/puzzles.but
@@ -1324,7 +1324,11 @@
used to select a peg colour, the left and right keys to select a
peg position, and the space bar or Enter key to place a peg of the
selected colour in the chosen position. \q{D} or Backspace removes a-peg, and \q{H} adds a hold marker.+peg, and Space adds a hold marker.
+
+Pressing \q{h} or \q{?} will fill the current guess with a suggested+guess. Using this is not recommended for 10 or more pegs as it is
+slow.
When the guess is complete, the smaller feedback pegs will be highlighted;
clicking on these (or moving the peg cursor to them with the arrow keys