Abstract Class

void setup(){
  size(140, 30);
  background (255, 0, 102);
  Shape s= new Square("Shape a",4.5d);
  text((s.ToString()), 10, 15);
}
abstract class Shape{
  String Name;
  abstract double Perimeter();
  String GetName(){
     return Name;
  }
 String ToString(){
    return GetName() + " Square = " + Perimeter();
  }
}
class Square extends Shape{
  double h;
  Square(String n,double h){
    Name = n;
    h = h;
  }
  double Perimeter(){
  return 4*h;
  }
}