#include <iostream> using namespace std; const double Pi=3.1415926; class Circle { public: void setRadius(double r); //半径 double area(); //面积 double circumference(); //周长 private: double radius; }; void Circle::setRadius(double r) //半径 { radius=r; } double Circle::area() //面积 { return Pi * radius * radius; } double Circle::circumference() //周长 { return 2*Pi*radius; } int main() { double r; cout<<"请输入旱冰场的半径: "; cin>>r; Circle c; c.setRadius(r); cout<<"旱冰场的造价为 "<<20*c.area()+35*c.circumference()<<" 元。"<<endl; return 0; }
运行结果
心得体会
终于有对象了