ai_lab_10

global N
N = 4
def printSolution(board):
for i in range(N):
for j in range(N):
if board[i][j] == 1:
print("Q", end= " ")
else:
print("-", end= " ")
print()
def isSafe(board, row, col):
#check column above
for i in range(row):
if board[i][col] == 1:
return False
#check upper left diagonal
for i, j in zip(range(row, -1, -1),range(col, -1, -1)):
if board[i][j] == 1:
return False
#check upper right diagonal
for i, j in zip(range(row, -1, -1),range(col, N)):
if board[i][j] == 1:
return False
return True
def solveNQUtil(board, row):
if row >= N:
return True
for i in range(N):
if isSafe(board, row, i):
board[row][i] = 1
if solveNQUtil(board, row + 1) == True:
return True
board[row][i] = 0
return False
def solveNQ():
board = [[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0]]
if solveNQUtil(board, 0) == False:
print("Solution does not exist")
return False
printSolution(board)
return True
solveNQ()