第5题

来源：互联网发布：vue.js if else 编辑：程序博客网时间：2024/05/20 08:27
#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(12.6);                                             Square square(3.5);                                               Rectangle rectangle(4.5,8.4);                                    Trapezoid trapezoid(2.0,4.5,3.2);                                 Triangle triangle(4.5,8.4);                                       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;    return 0;} <img src="http://img.blog.csdn.net/20150609201654679?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvYmluZzA1Mjg=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
0 0