Virtual Function.

Write a C++ program to implement runtime polymorphism through virtual function. 

Algorithm:

Step 1: Start the program

Step 2: Declare a base class called base

Step 3: Declare a derived class of class base

Step 4: In the main function create object for base and derived class

Step 5: Assign base ptr to base class object

Step 6: Assign base ptr to derived class object

Step 7: Invoke the particular functions

Step 8: Stop the program

Program Code:

#include<iostream.h>

#include <conio.h>

class base

{

public:

void display()

{

cout<<"display base class\n";

}

virtual void show()

{

cout<<"Show Base\n";

}

};

class derived :public base

{

public: void display()

{

cout<<"display derived class\n";

}

void show()

{

cout<<" show derived\n";

}

};

int main()

{

base b;

derived d;

base *bptr;

clrscr();

cout<<"\n bptr points to base\n";

bptr=&b;

bptr->display();

bptr->show();

cout<<"\n\n bptr points to derived\n";

bptr=&d;

bptr->display();

bptr->show();

getch();

return 0;

}

Output:

bptr points to base

display base class

Show Base

display base class

show derived