public class suduko { static int N = 9; static boolean solveSuduko(int grid[][], int row,int col){ if (row == N - 1 && col == N) return true; if (col == N) { row++; col = 0; } if (grid[row][col] != 0) return solveSuduko(grid, row, col + 1); for (int num = 1; num < 10; num++) { if (isSafe(grid, row, col, num)) { grid[row][col] = num; if (solveSuduko(grid, row, col + 1)) return true; } grid[row][col] = 0; } return false; } static void print(int[][] grid) { for (int i = 0; i < N; i++) { for (int j = 0; j < N; j++) System.out.print(grid[i][j] + " "); System.out.println(); } } static boolean isSafe(int[][] grid, int row, int col, int num) { for (int x = 0; x <= 8; x++) if (grid[row][x] == num) return false; for (int x = 0; x <= 8; x++) if (grid[x][col] == num) return false; int startRow = row - row % 3, startCol= col - col % 3; for (int i = 0; i < 3; i++) for (int j = 0; j < 3; j++) if (grid[i + startRow][j + startCol] == num) return false; return true; } // Driver Code public static void main(String[] args) { int grid[][] = { { 5, 3, 0, 0, 7, 0, 0, 0, 0 }, { 6, 0, 0, 1, 9, 5, 0, 0, 0 }, { 0, 9, 8, 0, 0, 0, 0, 6, 0 }, { 8, 0, 0, 0, 6, 0, 0, 0, 3 }, { 4, 0, 0, 8, 0, 3, 0, 0, 1 }, { 7, 0, 0, 0, 2, 0, 0, 0, 6 }, { 0, 6, 0, 0, 0, 0, 2, 8, 0 }, { 0, 0, 0, 4, 1, 9, 0, 0, 5 }, { 0, 0, 0, 0, 8, 0, 0, 7, 9 }, }; if (solveSuduko(grid, 0, 0)) print(grid); else System.out.println("No Solution exists"); } }