PROGRAM FOR RUNTIME POLYMORPHISM

//program for runtime time polymorphism
#include<iostream.h>
#include<conio.h>
#include<string.h>
class media
{
protected:
char title[50];
float price;
public:
media(char *s,float a)
{
  strcpy(title,s);
  price=a;
}
virtual void display()
{}
};
class book:public media
{
  int pages;
  public:
  book(char *s,float a,int p):media(s,a)
  {
  pages=p;
  }
  void display();
};
class tape:public media
{
float time;
public:
tape(char *s,float a,float t):media(s,a)
{
  time=t;
}
void display();
};
void book::display()
{
  cout<<"\ntitle:"<<title;
  cout<<"\npages:"<<pages;
  cout<<"\nprice:"<<price;
}
void tape::display()
{
  cout<<"\ntitle:"<<title;
  cout<<"\nplaytime:"<<time;
  cout<<"\nprice:"<<price;
}
void main()
{
 char*title=new char[30];
 float price,time;
 int pages;
 clrscr();
 cout<<"\nenter book details\n";
  cout<<"\ntitle:";cin>>title;
  cout<<"\npages:";cin>>pages;
  cout<<"\nprice:";cin>>price;
  book book1(title,price,pages);
 cout<<"\nenter tape details\n";
  cout<<"\ntitle:";cin>>title;
  cout<<"\nplaytime:";cin>>time;
  cout<<"\nprice:";cin>>price;
  tape tape1(title,price,time);
  media *list[2];
  list[0]=&book1;
  list[1]=&tape1;
  cout<<"\nmedia details";
  cout<<"\n....book.....";
  list[0]->display();
  cout<<"\n....tape.....";
  list[1]->display();
  getch();
 }