http://stackoverflow.com/questions/28573479 sample code

Classes.h

#ifndef __BaseClass__
#define __BaseClass__
#include <stdio.h>
#include <stdlib.h>
#include <string>
using namespace std;
class BaseClass
{
    public:
        BaseClass(){};
        virtual ~BaseClass(){};
        virtual void SetName(string name){printf("in base set name\n");}
        virtual float Evaluate(float time){printf("in base Evaluate\n");return 0;}
        virtual bool DataExists(){printf("in base data exists\n");return false;}
};
#endif /* defined(__BaseClass__) */
#ifndef __DerivedClass__
#define __DerivedClass__

#include "BaseClass.h"

class DerivedClass:public BaseClass
{
    public:
        DerivedClass(){};
        virtual ~DerivedClass(){};
        virtual float Evaluate(float time){printf("in derived Evaluate\n");return 1;}
        virtual bool DataExists(){printf("in derived data exists\n");return true;}
        virtual void MyFunction(){printf("in my function\n");}
        virtual void SetObject(BaseClass *input){printf("in set object\n");}
};
#endif /* defined(__DerivedClass__) */

#ifndef __NextDerivedClass__
#define __NextDerivedClass__

#include "DerivedClass.h"

class NextDerivedClass:public DerivedClass
{
    public:
        NextDerivedClass(){};
        virtual ~NextDerivedClass(){};
        virtual void SetObject(BaseClass *input){printf("in set object of next derived class\n");}
};
#endif /* defined(__NextDerivedClass__) */