Merge pull request #2185 from sujurinki/master

N QUEEN IN PYTHON

N QUEEN.py

@@ -0,0 +1,68 @@
+
+global N
+N = 4
+
+def printSolution(board):
+	for i in range(N):
+		for j in range(N):
+			print(board[i][j], end = " ")
+		print()
+
+def isSafe(board, row, col):
+
+
+	for i in range(col):
+		if board[row][i] == 1:
+			return False
+
+	for i, j in zip(range(row, -1, -1),
+					range(col, -1, -1)):
+		if board[i][j] == 1:
+			return False
+
+	for i, j in zip(range(row, N, 1),
+					range(col, -1, -1)):
+		if board[i][j] == 1:
+			return False
+
+	return True
+
+def solveNQUtil(board, col):
+
+	if col >= N:
+		return True
+
+	for i in range(N):
+
+		if isSafe(board, i, col):
+
+
+			board[i][col] = 1
+
+
+			if solveNQUtil(board, col + 1) == True:
+				return True
+
+
+			board[i][col] = 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()
+
+