java12周第一题

interface A{
 public void print();
}
class Rectangle implements A{
 int chang=5;
 int kuan=6;
 int mianji,zhouchang;
 public void print() {
  mianji=5*6;
  zhouchang=2*(chang+kuan);
  System.out.println("矩形的面积为："+mianji+"     矩形的周长为："+zhouchang);
 }
}
 class Circle implements A{
  double pi=3.1415,r=2;
  double mianji,zhouchang;
  public void print() {
   mianji=pi*r*r;
    zhouchang = (2*pi*r);
   System.out.println("圆形的面积为："+mianji+"     圆形的周长为："+zhouchang);
  }
  
 }
 class Square implements A{
  int a=4;
  int mianji,zhouchang;
  public void print() {
   mianji=a*a;
   zhouchang=2*(a+a);
   System.out.println("正方形的面积为："+mianji+"    正方形的周长为："+zhouchang);
  }
 }

public class Shape {

 public static void main(String[] args) {
  Rectangle p1=new Rectangle();
  Circle    p2=new Circle();
  Square    p3=new Square();
  p1.print();
  p2.print();
  p3.print();

 }

}