class GenericShape { 
  void draw() {
      System.out.println( this + "Generic Draw");
  }
  void erase() {
      System.out.println(this + "Generic Erace");
  } 
}

class Circle2 extends GenericShape {
  public String toString() { 
       return "Circle "; 
  }
  void draw() { 
    System.out.println("Circle Draw"); 
  }
  void erase() { 
    System.out.println("Circle Erase"); 
  }
}

class Square2 extends GenericShape {
  public String toString() { 
       return "Square "; 
  }
  void erase() { 
    System.out.println("Square Erase"); 
  }

}

class Triangle2 extends GenericShape {
  public String toString() { 
       return "Triangle "; 
  }
  void draw() { 
    System.out.println("Triangle Draw"); 
  }
}

public class Shapes2 {
  public static GenericShape randShape() {
    switch((int)(Math.random() * 3)) {
      default:
      case 0: return new Circle2();
      case 1: return new Square2();
      case 2: return new Triangle2();
    }
  }
  public static void main(String[] args) {
    GenericShape[] s = new GenericShape[4];
    // Fill up the array with shapes:
    for(int i = 0; i < s.length; i++)
      s[i] = randShape();
    // Make polymorphic method calls:
    for(int i = 0; i < s.length; i++){
      s[i].draw();
      s[i].erase();
    }
  }
} ///:~