circle.h

谭浩强 《C++ 程序设计》第三版的部分课后练习题源码

class Circle:public Point
{
      protected:
              float r;
             
      public:
             Circle(float a,float b,float c):Point(a,b),r(c){}
             float area()const;
             void showname()const { cout<<"the information of the circle :"; }
             void display()const;
      
      
};