public class SortedLists {
  public static void main(String[] args) {

    SortedLinkedList sll = null;
    for (int i = 0; i < 2; i++) {
      if (i == 0)
        sll = new SortedSinglyLinkedList();
      else
        sll = new SortedDoublyLinkedList();
        
      sll.insert("Alle");
      sll.insert("meine");
      sll.insert("Entchen");
      sll.insert("schwimmen");
      sll.insert("auf");
      sll.insert("dem");
      sll.insert("See");
      System.out.println(sll);
      System.out.println("---");
    }
  }
}