[LeetCode] NQueen

public class Solution {
    public int totalNQueens(int n) {
        if (n<=0) return 0;
        int [] locations;
        locations = new int[n];

        return findNQueens(locations, 0);        
    }
    
        public int findNQueens(int [] locations, int row) {
        if (row == locations.length) {
            //printNQueens(locations);
            return 1;
        }

        int result = 0;
        for(int i=0; i<locations.length; i++) {
            if (check(locations, row, i)) {
                locations[row] = i;
                result += findNQueens(locations, row+1);
            }
        }
        return result;
    }

    public boolean check(int [] locations, int row, int clom) {
        for (int i=0; i<row; i++) {
            if (locations[i] == clom) return false;
            if (locations[i]+i == row+clom) return false;
            if (i-locations[i] == row-clom) return false;
        }

        return true;
    }
}