Jav G-queen Extra Quality May 2026

The N-Queens problem is a classic backtracking problem in computer science, where the goal is to place N queens on an NxN chessboard such that no two queens attack each other.

The space complexity of the solution is O(N^2), where N is the number of queens. This is because we need to store the board configuration and the result list. jav g-queen

Given an integer n , return all possible configurations of the board where n queens can be placed without attacking each other. The N-Queens problem is a classic backtracking problem

The backtrack method checks if the current row is the last row, and if so, adds the current board configuration to the result list. Otherwise, it tries to place a queen in each column of the current row and recursively calls itself. Given an integer n , return all possible

private boolean isValid(char[][] board, int row, int col) { // Check the column for (int i = 0; i < row; i++) { if (board[i][col] == 'Q') { return false; } } // Check the main diagonal int i = row - 1, j = col - 1; while (i >= 0 && j >= 0) { if (board[i--][j--] == 'Q') { return false; } } // Check the other diagonal i = row - 1; j = col + 1; while (i >= 0 && j < board.length) { if (board[i--][j++] == 'Q') { return false; } } return true; } }