My sudoku solver replaces "-" with zeros, then solves the puzzle. It works for most puzzles that I've tried, but throws an ArrayIndexOutOfBoundsException for puzzles with a full row of dashes. I've tried tweeking different things to get it to work, but I'm a little lost.
This is what the puzzle looks like.
public static int[][] theArray = new int [9][9];
public static int SIZE = 9;
private static boolean isCompletePuzzle() {
// checks for 0 in rows/cols
for (int i = 0; i <= SIZE; i++) {
for (int j = 0; j <= SIZE; j++) {
if (theArray[i][j] != 0) {
return true;
}
}
}
return false;
}
private static boolean isValidPuzzle(int row, int col, int number) {
// checks rows
for (int i = 0; i < SIZE; i++) {
if (theArray[row][i] == number) {
return true;
}
}
// checks columns
for (int i = 0; i < SIZE; i++) {
if (theArray[i][col] == number) {
return true;
}
}
// checks 3x3
int r = row - row % 3;
int c = col - col % 3;
for (int i = r; i < r + 3; i++)
for (int j = c; j < c + 3; j++)
if (theArray[i][j] == number)
return true;
return false;
}
private static boolean isSolvedPuzzle(int row, int col, int number) {
if (isValidPuzzle(row, col, number) == true && isCompletePuzzle() == true) {
return true;
}
return false;
}
public static boolean solvePuzzle() {
for (int row = 0; row < SIZE; row++) {
for (int col = 0; col < SIZE; col++) {
if (theArray[row][col] == 0) {
for (int number = 1; number <= SIZE; number++) {
if (!isSolvedPuzzle(row, col, number)) {
theArray[row][col] = number;
if (solvePuzzle()) {
return true;
}
else {
theArray[row][col] = 0;
}
}
}
return false;
}
}
}
return true;
}
