cpp课程设计实验题：编写程序，定义抽象基类Shape(形状)，由它派生出3个派生类: Circle(圆形)、Rectangle(矩形)和Square 正方形)，用函数函数ShowArea分别显
#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 3.14*radius*radius;};
void ShowArea()
{
cout<<"圆形的面积为："<<area()<<endl;
}
protected:
double radius;
};
class Rectangle:public Shape
{
public:
Rectangle(double w,double h):width(w),height(h){}
virtual double area() const {return width*height;}
void ShowArea()
{
cout<<"矩形的面积为："<<area()<<endl;
}
protected:
double width,height;
};
class Square:public Shape
{
public:
Square(double w):width(w){}
virtual double area() const {return width*width;}
void ShowArea()
{
cout<<"正方形的面积为："<<area()<<endl;
}
protected:
double width;
};
int main()
{
Circle c1(5);
c1.ShowArea();
Rectangle r1(5,6);
r1.ShowArea();
Square t1(4);
t1.ShowArea();
Shape *pt[3]={&c1,&r1,&t1};
double areas=0.0;
for(int i=0;i<3;i++)
{
areas=areas+pt[i]->area();
}
cout<<"总面积为："<<areas<<endl;
return 0;
//This code was written by gfh in SCMZU.
}