public class RectanglePoly
{
  public static void main(String args[]){
    // This alias can point to all Rectangles and its sub classes
    Rectangle r;

    if(args[0].equals("rectangle")){
      r = new Rectangle(20, 10);
    }else{
      r = new Parallelogram3(20, 10, 1);
    }
    
    r.printDetails();
  }
}