第五题

来源：互联网发布：淘宝卖什么产品利润高编辑：程序博客网时间：2024/05/04 02:08

#include <iostream>using namespace std;class Shape{public: virtual double area() const =0;                            };class Circle:public Shape{public:Circle(double r):radius(r){}                                   virtual double area() const {return 3.14159*radius*radius;};    protected:  double radius;                                              };class Square:public Shape{public:  Square(double s):side(s){}                                     virtual double area() const {return side*side;}              protected:  double side;};class Rectangle:public Shape{public: Rectangle(double w,double h):width(w),height(h){}               virtual double area() const {return width*height;}             protected:  double width,height;                                        };class Trapezoid:public Shape{public:  Trapezoid(double t,double b,double h):top(t),bottom(t),height(h){}   virtual double area() const {return 0.5*(top+bottom)*height;}      protected:  double top,bottom,height;                                         };class Triangle:public Shape{public:  Triangle(double w,double h):width(w),height(h){}                 virtual double area()const {return 0.5*width*height;}           protected:  double width,height;                                           };int main(){ Circle circle(10);                                            Square square(3.5);                                            Rectangle rectangle(4.5,8.0);                                     Trapezoid trapezoid(2.0,4.5,3.2);                             Triangle triangle(4.5,8.0);                                     Shape *pt[5]={&circle,&square,&rectangle,&trapezoid,&triangle};                                                 double areas=0.0;                                               for(int i=0;i<5;i++)  {areas=areas+pt[i]->area();} cout<<"totol of all areas="<<areas<<endl;  cout<<"circle,square,rectangle,trapezoid,triangle"<<endl; for(int j=0;j<5;j++) { cout<<"area="<<pt[j]->area()<<endl;; } return 0;}

<img src="http://img.blog.csdn.net/20150526174002476?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvbW9sdXpodWk=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />

0 0