这段代码编译通过，课时结果居然显示函数错误？！！

public class TestShape {
    static public void mian(String[] args){
        Shape[] s=new Shape[2];
        s[0]=new Rect(3,4);
        s[1]=new Circle(2);
        for(int i=0;i<s.length;i++){
            System.out.println(s.sqr());
            System.out.println(s.per());
        }
    }
}
class Shape{
    public Shape(){}
    public double sqr(){
        return 0;
    }
    public double per(){
        return 0;
    }    
}
class Rect extends Shape{
    private double x;
    private double y;
    public Rect(){}
    public Rect(double x,double y){
        this.x=x;
        this.y=y;
    }
    public double sqr(){
        return x*y;
    }
    public double per(){
        return (x+y)*2;
    }
}
class Circle extends Shape{
    private double r;
    public Circle(){}
    public Circle(double r){
        this.r=r;
    }
    public double sqr(){
        return r*r*3.1415926535;
    }
    public double per(){
        return r*2*3.1415926535;
    }
}

代码在这，求解释

这代码也能编译过，真的假的啊。。。。。。。

复制代码 static public void mian(String[] args)

应改为：

复制代码 public static void main(String[] args)

复制代码 System.out.println(s.sqr()); System.out.println(s.per());

应改为：

复制代码 System.out.println(s[i].sqr()); System.out.println(s[i].per());

未测试，你试试看吧，没法解释