circle.h

c++小程序

double const pi=3.141592653;
class Circle
{
	double R;
	public:
		double Init(double InitR);
		double GetR(){return R;}
		double Area(double R){return pi*R*R;}
		double S(double R){return 2*pi*R;}
		void display();
};
double Circle::Init(double InitR)
{
	R=InitR;
	return R;
}
void Circle::display()
{
	cout<<"半径"<<GetR()<<"面积"<<Area(R)<<endl;
}