用面向对象的方法进行设计

雨点打透心脏的1/2处 2022-07-26 05:07 92阅读 0赞

编写一个与图形相关的应用程序，需要处理大量图形（Shape）的信息。图形有矩形（Rectangle），圆形（Circle）和正方形（Square），应用需要计算这些图形的面积并且可能在设备上进行显示。

#include <map>
    #include <queue>
    #include <stack>
    #include <cmath>
    #include <cstdio>
    #include <cstring>
    #include <iostream>
    #include <algorithm>
    
    
    using namespace std ;
    
    
    #define PI 3.14159
    
    
    class Shape
    {     //抽象类
    public:
        Shape(){}
        ~Shape(){}
        virtual void Draw() = 0 ; //纯虚函数
        virtual double Area() = 0 ; //纯虚函数
    } ;
    
    
    //长方形类
    class Rectangle : public Shape
    {
    private:
        int a;
        int b;
    public:
        Rectangle():a(0),b(0){}
        Rectangle(int x,int y):a(x),b(y){}
        virtual void Draw()
        {
            cout<<"Retangle , Area = "<<Area()<<endl;
        }
        virtual double Area()
        {
            return a*b ;
        }
    } ;
    
    
    //圆形类
    class Circle : public Shape
    {
    private:
        double r;
    public:
        Circle(double x):r(x){}
        virtual void Draw()
        {
            cout<<"Circle , Area = "<<Area()<<endl;
        }
        virtual double Area()
        {
            return r*r*PI;
        }
    } ;
    
    
    //正方形类,继承Rectangle类
    class Square : public Rectangle
    {
    private:
        int a ;
    public:
        Square(int x):a(x){}
        virtual void Draw()
        {
            cout<<"Square , Area = "<<Area()<<endl;
        }
        virtual double Area()
        {
            return a*a;
        }
    } ;
    
    
    int main()
    {
        Rectangle rect(10,20);
        Square square(10);
        Circle circle(8);
    
    
        Shape *p ;  //基类(抽象类)指针
        p = &rect ;
        cout<<p->Area()<<endl;
        p->Draw();
    
    
        p = &square ;
        cout<<p->Area()<<endl;
        p->Draw();
    
    
        p = &circle ;
        cout<<p->Area()<<endl;
        p->Draw();
    
    
        return 0 ;
    }