import java.lang.Math;     /* to take square roots later on     */
import java.util.Vector;   /* to access the Vector class        */

class Figurettes
{
/*  *********************************************************** */
/*  Main method. Should not include any methods other than main */
/*  *********************************************************** */
   public static void main(String[] args)
   {
      Rectangle r   = new Rectangle("rectangle");
      Square    s   = new Square("square extends rectangle");
      Triangle  t   = new Triangle("right triangle");
      Vector    all = new Vector();

      r.setParameters(2.0, 4.0);     /* setting up the parameters */
      s.setParameters(3.0);          /* for each of the objects   */
      t.setParameters(3,4);

      all.addElement(r);             /* adding object to the      */
      all.addElement(s);             /* vector of all objects     */
      all.addElement(t);

      for (int i = 0; i < 3; i++)    /* for loop, notice the i++  */
      {
         Figure f = (Figure)(all.elementAt(i));  /* new variable  */
         /*            ^---------------------- using type casting */

         f.computeArea();            /* uses correct method for   */
         f.computePerimeter();       /* the object automatically  */
         f.display(); 
      }
   }
}