CODE 81. N-Queens II

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Follow up for N-Queens problem.
Now, instead outputting board configurations, return the total number of distinct solutions.

public int totalNQueens(int n) {
	// Note: The Solution object is instantiated only once and is reused by
	// each test case.
	int[] cols = new int[n];
	for (int i = 0; i < n; i++) {
		cols[i] = -1;
	}
	int number = createNQueens(n, cols, 0);
	return number;

}

public int createNQueens(int n, int[] rows, int row) {
	int number = 0;
	for (int i = 0; i < n; i++) {
		int j;
		for (j = 0; j < row; j++) {
			if (rows[j] == i || (row - j == Math.abs(rows[j] - i))) {
				break;
			}
		}
		if (j < row) {
			continue;
		}
		rows[row] = i;
		if (row == n - 1) {
			rows[row] = -1;
			return 1;
		} else {
			int tmp = createNQueens(n, rows, row + 1);
			number += tmp;
		}
		rows[row] = -1;

	}
	return number;
}