package pubs;

class Nil extends LinkedList {
      LinkedList copy() {
	  return this;
      }
    /*		
      List add(int e){
	  Cons aux = new Cons();
	  aux.elem = e;
	  aux.next = this;
	  return aux;
      }
    */
    /*		
      String print(){
       	  return "";
      }
    */
}