#include <iostream>
using namespace std;
class circle{
private:
double m_r;//成员变量
public:
void setR(double r)//成员函数
{
m_r = r;
}
double getR()
{
return m_r;
}
double getS()
{
return 3.14*m_r*m_r;
}
};
void main()
{
circle c1;
c1.setR(4);
cout << "r:" << c1.getR() << "s:" << c1.getS() << endl;
c1.setR(5);
cout << "r:" << c1.getR() << "s:" << c1.getS() << endl;
system("pause");
}