计算圆的继承类球的面积和体积---java与C++

public class Circle {

    private double radius;

    public double getRadius() {
        return radius;
    }

    public void setRadius(double radius) {
        this.radius = radius;
    }
}

public class Ball extends Circle{

     public double Area(){
         return this.getRadius()*this.getRadius()*4*3.1415926;
     }

     public double Area2(){
         return (4/3)*3.1415926*this.getRadius()*this.getRadius()*this.getRadius();
     }
}```

```java
public class Main {

    public static void main(String []args){
        Ball ball = new Ball();
        ball.setRadius(4.13);
        System.out.println(ball.Area());
        System.out.println(ball.Area2());
    }
}

#pragma once
using namespace std;
class circle {
private:
	double radius;
public:
	circle();
	~circle();
	double area();
	double area2();
	double getRadius();
	void setRadius(double radiusOne);


};```

```cpp
#include "circle.h"
circle::circle() {}
circle::~circle(){}

//静态成员
double circle::getRadius() {
	return radius;
}
void circle::setRadius(double radiusOne) {
	radius = radiusOne;
}```

```cpp
#pragma once
#include "circle.h"
class ball :public circle
{
 public:
	virtual double area();
	virtual double area2();

};```

```cpp
#include "ball.h"
double ball::area() {
	return getRadius() * getRadius() * 4 * 3.1415926;
}

double ball::area2() {
	return (4 / 3) * 3.1415926 * getRadius() * getRadius() * getRadius();
}```

```cpp
#include "ball.h"
#include 
using namespace std;
int main() {

	ball *one = new ball();
	one->setRadius(4.17);
	std::cout << one->getRadius() << std::endl;
	std::cout << one->area() << std::endl;
	std::cout << one->area2() << std::endl;


}```