// function for adding element to respective list
  public static void add_list(mtproject2 list1, mtproject2 list2, mtproject2 list3, int element) {
    int s1, s2, s3, res;

    s1 = list1.sizeof();
    s2 = list2.sizeof();
    s3 = list3.sizeof();

    res = find_small(s1, s2, s3);

    if (res == s1) {
      list1.final_add(element);
      // list1.bubbleSort();
      System.out.println("Added" + " " + element + " " + "to L1");
    } else if (res == s2) {
      list2.final_add(element);
      // list2.bubbleSort();
      System.out.println("Added" + " " + element + " " + "to L2");
    } else if (res == s3) {
      list3.final_add(element);
      // list2.bubbleSort();
      System.out.println("Added" + " " + element + " " + "to L3");
    }
  }