Calculating factorial using recursion.

Factorial_Recursion.cpp

#include <iostream.h>  
#include <conio.h>  
long factorial(int n)    
{    
     if(n==0)    
          return 1;    
     else    
          return n * factorial(n-1);    
}  
void main()    
{   
     cout<<factorial(5);    
     getch(); //To pause program in some compilers    
}  

This is for Turbo C++. Very Old Indeed.