Add a way to restart your puzzle from the beginning.

a2sudoku/game.c

@@ -66,6 +66,32 @@ void refreshPos(tPos x, tPos y)
 }
 
 
+void restartGame(void)
+{
+    tPos x, y;
+    tGameSquare *square;
+    
+    for (y = 0; y < BOARD_SIZE; y++) {
+        for (x = 0; x < BOARD_SIZE; x++) {
+            square = &(SQUARE_XY(x, y));
+            
+            if (square->knownAtStart)
+                continue;
+            
+            if ((square->value == EMPTY_SQUARE) &&
+                (square->scratchValues == 0))
+                continue;
+            
+            square->value = EMPTY_SQUARE;
+            square->scratchValues = 0;
+            square->correct = false;
+            square->invalid = false;
+            refreshPos(x, y);
+        }
+    }
+}
+
+
 void startGame(tDifficulty difficulty, tUpdatePosCallback callback)
 {
     tPos x, y;

a2sudoku/game.h

@@ -43,6 +43,8 @@ extern bool toggleScratchValueAtPos(tPos x, tPos y, tSquareVal val);
 // Returns false if the last move cannot be undone.
 extern bool undoLastMove(void);
 
+extern void restartGame(void);
+
 extern void saveGame(void);
 
 extern bool loadGame(tUpdatePosCallback callback);

a2sudoku/ui.c

@@ -282,14 +282,14 @@ void displayInstructions(void)
            "toggle a scratch value.  Press 0 to\n"
            "clear a square.  Play ends when the\n"
            "puzzle is solved.\n"
-           "\n"
            "    Difficulty          : %s\n"
            "    Show invalid values : %s\n"
            "    Show wrong values   : %s\n"
            "\n"
            "Press escape or Q to quit at any time.\n"
            "Press O to change options.\n"
-           "Press R to start a new game.\n"
+           "Press R to restart the current game.\n"
+           "Press N to start a new game.\n"
            "Press H to see this info again.\n"
            "Press U to undo your last move.\n"
            "  Press O to change options now or any\n"
@@ -597,6 +597,12 @@ bool playGame(void)
                 
             case 'r':
             case 'R':
+                shouldSave = false;
+                restartGame();
+                break;
+                
+            case 'n':
+            case 'N':
                 return true;
                 
             case 'q':