Shape.h

#ifndef?SHAPE_H
#define?SHAPE_H


class?Shape
{
????public:
????????Shape();
????????~Shape();

????????virtual?double?calcArea();

????protected:

????private:
};

#endif?//?SHAPE_H

Shape.cpp

#include?"Shape.h"
#include<iostream>
using?namespace?std;

Shape::Shape()
{
????cout<<"Shape()"<<endl;
}

Shape::~Shape()
{
????cout<<"~Shape()"<<endl;
}

virtual?double?Shape::calcArea()
{
????cout<<"Shape::calcArea()"<<endl;
????return?0;
}

Circle.h

#ifndef?CIRCLE_H
#define?CIRCLE_H

#include?"Shape.h"


class?Circle?:?public?Shape
{
????public:
????????Circle(double?r);
????????~Circle();

????protected:
????????double?m_dR;

????private:
};

#endif?//?CIRCLE_H

Circle.cpp

#include?"Circle.h"
#include<iostream>
using?namespace?std;

Circle::Circle(double?r)
{
????cout<<"Circle"<<endl;
????m_dR?=?r;
}

Circle::~Circle()
{
????cout<<"~Circle()"<<endl;
}

double?Circle::calcArea()
{
????cout<<"Circle::calcArea()"<<endl;
????return?3.14*m_dR*m_dR;
}

Rect.h

#ifndef?RECT_H
#define?RECT_H

#include?"Shape.h"


class?Rect?:?public?Shape
{
????public:
????????Rect(double?width,double?height);
????????~Rect();

????protected:
????????double?m_dWidth;
????????double?m_dHeight;

????private:
};

#endif?//?RECT_H

Rect.cpp

#include?"Rect.h"
#include<iostream>
using?namespace?std;

Rect::Rect(double?width,double?height)
{
????cout<<"Rect()"<<endl;
????m_dWidth?=?width;
????m_dHeight?=?height;
}

Rect::~Rect()
{
????cout<<"~Rect()"<<endl;
}

double?Rect::calcArea()
{
????cout<<"Rect::calcArea()"<<endl;
????return?m_dHeight*m_dWidth;
}

demo.cpp

#include<iostream>
using?namespace?std;
#include?"Rect.h"
#include?"Circle.h"


int?main()
{
????Shape?*shape1?=?new?Circle(4.3);
????Shape?*shape2?=?new?Rect(2.0,3.0);

????shape1->calcArea();
????shape2->calcArea();

????delete?shape1;
????shape1?=?NULL;
????delete?shape2;
????shape2?=?NULL;

????system("pause");

????return?0;
}

error:

D:\code\C++\C++遠(yuǎn)征之多態(tài)\計(jì)算面積\src\Circle.cpp|16|error: no 'double Circle::calcArea()' member function declared in class 'Circle'|

求大神指導(dǎo)！！