8-queens.py

# 8-Queen naive recursive search solution
# giraycoskun

import numpy as np

STATE_SET = []
SOLUTION_SET = []

def check_row(grid, i, k):
    for x in range(k,-1,-1):
        if grid[i][x] == 1:
            return False
    return True

def check_diagonal(grid, row, col):
    i = row
    k = col
    while i > -1 and k > -1:
        if grid[i][k] == 1:
            return False
        i -= 1
        k -= 1
    i = row
    k = col
    while i < 8 and k > -1:
        if grid[i][k] == 1:
            return False
        i += 1
        k -= 1
    return True

def successor(grid, k):
    for i in range(8):
        if check_diagonal(grid, i, k) and check_row(grid, i, k):
            res = grid.copy()
            res[i][k] = 1
            STATE_SET.append(res)
            if k == 7:
                SOLUTION_SET.append(res)
            if k<7:
                successor(res, k+1)
    
    

grid = np.zeros((8,8)) 
successor(grid, 0)
#print(SOLUTION_SET)
print(len(STATE_SET))
print(len(SOLUTION_SET))

with open("test.txt", 'w') as file:
    for item in STATE_SET:
        for x in item:
            file.write(str(x))
            file.write('\n')
        file.write('\n')
        file.write('\n')