#!/usr/bin/env python3

SIZE = 8
board = [0] * SIZE


def peaceful(k):
    if k < 1:
        return True
    for i in range(k):
        if board[i] == board[k]:
            return False
        if k - i == abs(board[k] - board[i]):
            return False
    return True


def main():
    num_sol = 0
    n = 0
    while n >= 0:
        if board[n] < SIZE:
            board[n] += 1
            if peaceful(n):
                if n < SIZE - 1:
                    n += 1
                else:
                    num_sol = num_sol + 1
                    print(str(board))
        else:
            board[n] = 0
            n -= 1
    print("Number of solutions: ", str(num_sol))


if __name__ == '__main__':
    main()