#include <iostream>
using namespace std;

//範例目的：練習繼承性（Inheritance），練習『父類別，子類別』 
//範例目的：要建立兩個類別：Shape,Circle 
///////////// 父類別：Shape
class Shape
{
private:
	double area;
	double girth;
public:
	Shape()
	{
		area = 0;
		girth = 0;
	}
	double getArea()
	{
		return area;
	}
};


/////////////// 子類別class：Circle 
//       繼承 : public Shape 
class Circle : public Shape
{
private:
	double radius;
public:
	void setRadiu(double myradius)
	{
		radius = myradius;
	}
};

//////////////////////
int main(int argc, char** argv) {
	//1.父類別Shape
	
	//2.子類別Cicle
	Circle a1;
	cout<<"area = "<<a1.getArea()<<endl;
	//注意：getArea()是父類別Shape的函數，所以circle已經繼承了
	 
	return 0;
}