package serie6;

object Main {

  def queens(n: int): List[List[int]] = {
    // ... ŕ compléter ...
    def placeQueens(k: int): List[List[int]] = {
      if (k == 0)
        List(List())
      else {
        for (
          val queens <- placeQueens(k - 1);
          val col <- List.range(1, n + 1);
          isSafe (col, queens, 1)
        ) yield col :: queens
      }
    }
    placeQueens(n);
  }

  def main(args: Array[String]): Unit = {
    // ... ŕ compléter ...
  }

}