Write a Scala program to replace every element with the next greatest element (from right side) in a given array of integers

object Scala_Array {

  def test(arr_nums: Array[Int]): Array[Int] = {
    val size = arr_nums.length;
    var max_from_right_num = arr_nums(size - 1);
    arr_nums(size - 1) = -1;
    var temp = 0
    for (i <- size - 2 to 0 by -1) {
      temp = arr_nums(i);
      arr_nums(i) = max_from_right_num;
      if (max_from_right_num < temp)
        max_from_right_num = temp;
    }
    arr_nums;
  }

  def main(args: Array[String]): Unit = {
    val nums = Array(45, 20, 100, 23, -5, 2, -6);
    println("Original array:");
    for (x <- nums) {
      print(s"${x}, ")
    }

    val result = test(nums);
    println("\nThe modified array:");
    for (x <- result) {
      print(s"${x}, ")
    }
  }
}