package w4.代码;

import w4.Rectangle;
import w4.Shape;
import w4.ShapeUtil;
import w4.Triangle;

public class Demo {
    public static void main(String[] args) {
        Shape circle = new Circle(5.0);
        Shape rectangle = new Rectangle(4.0, 6.0);
        Shape triangle = new Triangle(3.0, 4.0);

        ShapeUtil.printArea(circle);      // Area: 78.54
        ShapeUtil.printArea(rectangle);   // Area: 24.00
        ShapeUtil.printArea(triangle);    // Area: 6.00
    }
}