作业3.23

#include<iostream>using namespace std;class cylinder{public:void vol(){cout<<"这个圆柱体体积为："<<V<<endl;}     cylinder(double a,double b) { radius=a; high=b;      V=3.14159*(radius*radius)*high; }private:double radius;double high;

        double V;};int main(){cylinder p(10.5,2.0);

        p.vol();return 0;}