interface Silly {

   public void narf();

   public void poit(Silly s);

}


public class Bird implements Silly {

   public static void main(String args[]) {

     System.out.println("zero");

     Silly s = new SillyBird(1);

     Silly s2 = new Loony();

     s.poit(s2);

     s2.poit(s);

     System.out.println("zymurgy");

   }

   public Bird() {

     this(0);

     System.out.println("zircon");

   }

   public Bird(int i) {

     System.out.println("zanzibar");

   }

   public void narf() {

     System.out.println("zort");

   }

   public void poit(Silly s) {

      s.narf();

   }

}



class SillyBird extends Bird {

   public SillyBird() {

     System.out.println("duchess");

   }

   public SillyBird(int i) {

      super(i);

   }

   public void narf() {

      System.out.println("drum");

      super.narf();

   }

}



class Loony extends SillyBird {

   public Loony() {

      System.out.println("stupendous");

   }

   public void narf() {

     System.out.println("snark");

   }

}