其中坐标为(x,y)半径为r,输出计算圆的面积与周长的结果。
public class A {
public static void main(String[] args) {
Circle circle = new Circle(6);
circle.area();
circle.perimeter();
}
}
class Circle{
private int x = 0;
private int y = 0;
private double r = 0;
private final double PI = 3.14;
public Circle(double r) {
this.r = r;
}
public void area() {
System.out.println("面积:"+PI * r * r);
}
public void perimeter() {
System.out.println("周长:"+2 * PI * r);
}
}