❗️Что будет на выходе:

function recursiveNQueens(n) {
  const board = Array.from({ length: n }, () => Array.from({ length: n }, () => "."));
  const solutions = [];
  const isSafe = (row, col) => {
    for (let i = 0; i < row; i++) {if (board[i][col] === "Q") return false;
      const colOffset = row - i;
      if (col - colOffset >= 0 && board[i][col - colOffset] === "Q") return false;
      if (col + colOffset < n && board[i][col + colOffset] === "Q") return false;
 }
    return true;
  };

  const placeQueens = (row) => {
    if (row === n) {
      solutions.push(board.map(row => row.join("")));
      return;
    }
    for (let col = 0; col < n; col++) {
      if (isSafe(row, col)) {
        board[row][col] = "Q";
        placeQueens(row + 1);
        board[row][col] = ".";
      }
    }
  };
  placeQueens(0);
  return solutions;
}
const result = recursiveNQueens(4);

console.log(result);

Ответ: [[".Q..", "...Q", "Q...", "..Q."], ["..Q.", "Q...", "...Q", ".Q.."]]

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