3.23

3.23建立类cylinder,cylinder的构造函数被传递两个double值，分别表示圆柱体的半径和高度，用类cylinder计算圆柱体的体积，并储存在一个double变量中，在类cylinder中包含一个成员函数vol，用来显示每个cylinder对象的值。

#include<iostream>
using namespace std;
class Cylinder{
public:
Cylinder();
double vol(double h,double r);
private:
double high;
double radius;
};
Cylinder::Cylinder()
{
double h;
    double r;
high=h;
radius=r;
}
double Cylinder::vol(double h,double r)
{
high=h;
radius=r;
return 3.14*r*r*h;
}
int main()
{
    double h;
double r;
Cylinder cylinder6;
cout<<"输入圆柱体的高和底圆半径:"<<endl;
cin>>h>>r;
    cylinder6.vol(h,r);
cout<<"高为:"<<h<<"底圆半径为:"<<r<<"的圆柱体体积为:"<<cylinder6.vol(h,r)<<endl;
return 0;
}