求多边形的面积
1 #include<iostream>
2 using namespace std;
3 class CPolygon{
4 protected:
5 int width,height;
6 public:
7 void set_values(int a,int b)
8 {
9 width=a;height=b;}
10 };
11 class CRectangle:public CPolygon{
12 public:
13 int area()
14 {return (width*height);}
15 };
16 class CTriangle:public CPolygon{
17 public:
18 int area()
19 {return (width*height/2);}
20 };
21 int main()
22 {
23 CRectangle rect;
24 CTriangle trgl;
25 rect.set_values(4,5);
26 trgl.set_values(4,5);
27 cout<<rect.area()<<endl;
28 cout<<trgl.area()<<endl;
29 return 0;
30 }