package cn.edu.bjut.chapter4_1;

public class Circle extends Shape {
	private double radius; 
	
	public Circle(double radius) {
		this.radius = radius; 
	}

	@Override
	public double area() {
		return (Math.PI * radius * radius);
	}

	@Override
	public double perimeter() {
		return (2 * Math.PI * radius);
	}
}