import java.lang.*;
abstract public class Crispy extends Object{
//abstract classes can not have instances, but their extensions
//can have instances.  They describe common properties and state
//abstract functions that have to be defined for the extension
//to work...

  public static void main(String[]so_what){//adds milk to bowl
	Crispy bowl[] = {new Snap(), new Crackle(), new Pop() };

	for(int i = 0; i<bowl.length; i++)
		bowl[i].sound();

  }//main
  abstract public void sound();//all crispies make a sound
				//but we do not say what
}//Crispy

class Snap extends Crispy{
   public static void main(String[]so_what){//test
	new Snap().sound();
   }
   public void sound(){ System.out.println("Snap");}

}//Snap

class Crackle extends Crispy{
   public static void main(String[]so_what){//test
	new Crackle().sound();
   }
   public void sound(){ System.out.println("Crackle");}
}//Crackle

class Pop extends Crispy{
   public static void main(String[]so_what){//test
	new Pop().sound();
   }
   public void sound(){ System.out.println("Pop");}
}//Pop