1.      Program to use pointers for both base and derived classes and call the member functions using the `virtual` keyword.

1. #include <iostream.h>

2. #include<conio.h>

3. class Base {

4. public:

5.     virtual void show() {

6.                 cout << "Base class" << endl;

7.     }

8. };

9. class Derived : public Base {

10. public:

11.     void show() {

12.                 cout << "Derived class" << endl;

13.     }

14. };

15. int main() {

16.     Base *ptr;

17.     Derived obj;

18.     ptr = &obj; // Pointer to base class pointing to derived class object

19.     ptr->show(); // Calls the derived class's show() function due to virtual keyword

20.     getch();

21.     return 0;

22. }