// @topic T52015 11/27/2012 -- Inheritance and Polymorphism
// @brief Shape interface
#ifndef _SHAPE_H_INCLUDED_
#define _SHAPE_H_INCLUDED_
const double PI = 3.1415926;
class Shape {
public:
// polymorphic operations:
virtual ~Shape() {}
virtual void draw()=0;
virtual double area()=0;
};//class Shape
#endif // _SHAPE_H_INCLUDED_