3.23

#include<iostream>
#include<string>
using namespace std;
const double PI=3.14;
class cyclinder
{public:
double vol()
{cout<<"圆柱体的体积为："<<are()<<endl;
};
double are()
{return PI*radium*radium*high;}
cyclinder(double r,double h)
{high=h;
radium=r;
}


private:
double high;
double radium;
};




int main()
{cyclinder cyc1(2.5,3);
cyc1.are();
cyc1.vol();
cyclinder cyc2(3,4);
cyc2.are();
cyc2.vol();
return 0;
}