Sudoku

import random

def print_grid(grid):
for i in range(9):
if i % 3 == 0 and i != 0:
print("-" * 21)
for j in range(9):
if j % 3 == 0 and j != 0:
print("|", end=" ")
print(grid[i][j] if grid[i][j] != 0 else ".", end=" ")
print()

def is_valid(grid, row, col, num):
# Check row
if num in grid[row]:
return False

# Check column
for i in range(9):
    if grid[i][col] == num:
        return False

# Check 3x3 square
start_row, start_col = row - row % 3, col - col % 3
for i in range(3):
    for j in range(3):
        if grid[start_row + i][start_col + j] == num:
            return False
return True

def solve(grid):
for row in range(9):
for col in range(9):
if grid[row][col] == 0:
for num in range(1, 10):
if is_valid(grid, row, col, num):
grid[row][col] = num
if solve(grid):
return True
grid[row][col] = 0
return False
return True

def generate_sudoku():
grid = [[0 for _ in range(9)] for _ in range(9)]
for _ in range(15): # Fill some numbers randomly
row, col = random.randint(0, 8), random.randint(0, 8)
num = random.randint(1, 9)
if is_valid(grid, row, col, num):
grid[row][col] = num
return grid

Game

grid = generate_sudoku()
print("Welcome to Sudoku!")
print_grid(grid)

while True:
try:
row = int(input("Row (0-8): "))
col = int(input("Col (0-8): "))
num = int(input("Number (1-9): "))

    if grid[row][col] == 0 and is_valid(grid, row, col, num):
        grid[row][col] = num
        print_grid(grid)
    else:
        print("Invalid move!")
except ValueError:
    print("Please enter valid integers.")