作业6.12

#include <iostream>using namespace std;class area_c1{protected:double height;double width;public:area_c1(double r,double s){height=r; width=s;}virtual double area()=0;};class rectangle:public area_c1{public:rectangle(double r,double s):area_c1(r,s){}double area(){cout<<"该矩形的长为:"<<height<<endl;cout<<"该矩形的宽为:"<<width<<endl;cout<<"该矩形的面积为:"<<height*width<<endl;return 0;}};class isosceles:public area_c1{public:isosceles(double r,double s):area_c1(r,s){}double area(){cout<<"该三角形的高为:"<<height<<endl;    cout<<"该三角形的宽为:"<<width<<endl;cout<<"该三角形的面积为:"<<0.5*height*width<<endl;return 0;}};int main(){rectangle A (10.0,5.0);isosceles B (4.0,6.0);area_c1 *pr;pr=&A;pr->area();cout<<endl;pr=&B;pr->area();return 0;}