package cn.edu.bjut.chapter3;

public class Circle {
	private double r;
	public static final double PI = 3.14;

	public Circle(double r) {
		this.r = r;
	}

	public double area() {
		return (r * r * PI);
	}

	public static void main(String[] args) {
		Circle c1 = new Circle(2);
		Circle c2 = new Circle(3);
		System.out.println(c1.area() + "\t" + c2.area());
	}
}