New puzzle from James Harvey: 'Singles', an implementation of

Hitori. One infrastructure change in the process: latin.c has
acquired a utility function to generate a latin rectangle rather
than a full square.

[originally from svn r8828]

icons/Makefile

@@ -2,8 +2,8 @@
 
 PUZZLES = blackbox bridges cube dominosa fifteen filling flip galaxies guess \
 	  inertia keen lightup loopy map mines net netslide pattern pegs \
-	  rect samegame sixteen slant solo tents towers twiddle unequal \
-	  untangle
+	  rect samegame singles sixteen slant solo tents towers twiddle \
+	  unequal untangle
 
 BASE = $(patsubst %,%-base.png,$(PUZZLES))
 WEB = $(patsubst %,%-web.png,$(PUZZLES))
@@ -70,6 +70,7 @@ netslide-ibase.png : override CROP=289x289 144x144+0+0
 pattern-ibase.png : override CROP=384x384 223x223+0+0
 pegs-ibase.png : override CROP=263x263 147x147+116+0
 rect-ibase.png : override CROP=205x205 115x115+90+0
+singles-ibase.png : override CROP=224x224 98x98+15+15
 sixteen-ibase.png : override CROP=288x288 144x144+144+144
 slant-ibase.png : override CROP=321x321 160x160+160+160
 solo-ibase.png : override CROP=481x481 145x145+24+24

icons/singles.sav

@@ -0,0 +1,45 @@
+SAVEFILE:41:Simon Tatham's Portable Puzzle Collection
+VERSION :1:1
+GAME    :7:Singles
+PARAMS  :5:6x6dk
+CPARAMS :5:6x6dk
+SEED    :15:781273601054598
+DESC    :36:361566412253452144234115163346553461
+NSTATES :2:37
+STATEPOS:2:22
+MOVE    :4:B1,0
+MOVE    :4:C0,0
+MOVE    :4:C1,1
+MOVE    :4:C2,0
+MOVE    :4:C0,1
+MOVE    :4:B0,2
+MOVE    :4:C0,3
+MOVE    :4:C1,2
+MOVE    :4:C4,3
+MOVE    :4:B3,3
+MOVE    :4:C3,2
+MOVE    :4:C2,3
+MOVE    :4:C3,4
+MOVE    :4:B2,4
+MOVE    :4:C1,4
+MOVE    :4:C2,5
+MOVE    :4:B1,5
+MOVE    :4:C0,5
+MOVE    :4:C0,4
+MOVE    :4:C1,3
+MOVE    :4:C3,5
+MOVE    :4:B5,4
+MOVE    :4:C4,4
+MOVE    :4:C5,5
+MOVE    :4:C5,3
+MOVE    :4:C4,5
+MOVE    :4:B4,0
+MOVE    :4:C3,0
+MOVE    :4:C4,1
+MOVE    :4:C5,0
+MOVE    :4:C5,1
+MOVE    :4:B4,2
+MOVE    :4:C5,2
+MOVE    :4:C3,1
+MOVE    :4:B2,1
+MOVE    :4:C2,2

latin.c

@@ -1236,6 +1236,24 @@ digit *latin_generate(int o, random_state *rs)
     return sq;
 }
 
+digit *latin_generate_rect(int w, int h, random_state *rs)
+{
+    int o = max(w, h), x, y;
+    digit *latin, *latin_rect;
+
+    latin = latin_generate(o, rs);
+    latin_rect = snewn(w*h, digit);
+
+    for (x = 0; x < w; x++) {
+        for (y = 0; y < h; y++) {
+            latin_rect[y*w + x] = latin[y*o + x];
+        }
+    }
+
+    sfree(latin);
+    return latin_rect;
+}
+
 /* --------------------------------------------------------
  * Checking.
  */

latin.h

@@ -112,6 +112,9 @@ void latin_solver_debug(unsigned char *cube, int o);
 
 digit *latin_generate(int o, random_state *rs);
 
+/* The order of the latin rectangle is max(w,h). */
+digit *latin_generate_rect(int w, int h, random_state *rs);
+
 int latin_check(digit *sq, int order); /* !0 => not a latin square */
 
 void latin_debug(digit *sq, int order);

puzzles.but

@@ -2651,6 +2651,57 @@ level, some backtracking will be required, but the solution should
 still be unique. The remaining levels require increasingly complex
 reasoning to avoid having to backtrack.
 
+
+\C{singles} \i{Singles}
+
+\cfg{winhelp-topic}{games.singles}
+
+You have a grid of squares, all of which contain numbers. Your task
+is to colour some of the squares black (removing the number) so as to satisfy
+all of the following conditions:
+
+\b No number occurs more than once in any row or column.
+
+\b No black square is horizontally adjacent to any other black square.
+
+\b The remaining white squares must all form one contiguous region.
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-singles} who call it Hitori. 
+
+Singles was contributed to this collection by James Harvey.
+
+\B{nikoli-hitori}
+\W{http://www.nikoli.com/en/puzzles/hitori/index.html}\cw{http://www.nikoli.com/en/puzzles/hitori/index.html}
+(beware of Flash)
+
+\H{singles-controls} \i{Singles controls}
+
+\IM{Singles controls} controls, for Singles
+
+Left-clicking on an empty square will colour it black; left-clicking again 
+will replace the number. Right-clicking will add a circle (useful for 
+indicating that a cell is definitely not black). 
+
+You can also use the cursor keys to move around the grid. Pressing the
+return or space keys will turn a square black or add a circle respectively,
+and pressing the key again will replace the number or remove the circle.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{singles-parameters} \I{parameters, for Singles}Singles parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle.
+
+
 \A{licence} \I{MIT licence}\ii{Licence}
 
 This software is \i{copyright} 2004-2010 Simon Tatham.

singles.R

@@ -0,0 +1,23 @@
+# -*- makefile -*-
+
+SINGLES_EXTRA = dsf latin maxflow tree234
+
+singles : [X] GTK COMMON singles SINGLES_EXTRA singles-icon|no-icon
+singles : [G] WINDOWS COMMON singles SINGLES_EXTRA singles.res|noicon.res
+
+ALL += singles[COMBINED] SINGLES_EXTRA
+
+singlessolver : [U] singles[STANDALONE_SOLVER] SINGLES_EXTRA STANDALONE
+singlessolver : [C] singles[STANDALONE_SOLVER] SINGLES_EXTRA STANDALONE
+
+!begin gtk
+GAMES += singles
+!end
+
+!begin >list.c
+    A(singles) \
+!end
+
+!begin >wingames.lst
+singles.exe:Singles
+!end