ShapeSumArea.java

import java.util.*;

public class ShapeSumArea {

	public static void main(String[] args) {
		Rect2D rect1 = new Rect2D(10, 20);
		Circle2D circle1 = new Circle2D(3);
		Rect2D rect2 = new Rect2D(10, 4);
		Circle2D circle2 = new Circle2D(5);
		Circle2D circle3 = new Circle2D(6);
		ArrayList list = new ArrayList();
		list.add(rect1);
		list.add(circle1);
		list.add(rect2);
		list.add(circle2);
		list.add(circle3);
		double sum = 0;
		for (int i = 0; i < list.size(); i++) {
			Shape s = (Shape) list.get(i);
			sum += s.getArea();
		}
		System.out.println(sum);
	}

}