摘要： #include"iostream.h"#include "math.h"class cir{public:void j(){cout<<"圆的半径：";cin>>a;} void h(){ area=3.1415926*a*a; cout<<"圆的半径:"<<area<<endl;}private:double a,area;};void main(){cir i; i.j(); i.h();}求圆的面积,也是类定义的!!在第一函数输入圆的半径,第二个函 阅读全文