time O(N!)
space O(N^2)
State Variables
solutionsFound0
Initialize 4x4 board to place 4 queens.
Pseudocode
Pseudocode
1function solveNQueens(n):
2 board = empty nxn grid
3 solutions = 0
4 function backtrack(row):
5 if row == n:
6 solutions++
7 return
8 for col from 0 to n-1:
9 if isSafe(board, row, col):
10 board[row][col] = 'Q'
11 backtrack(row + 1)
12 board[row][col] = empty
13 backtrack(0)
14 return solutions