Fibonacci series

/*
      program to generate Fibonacci series in C++.
 */

 

#include<iostream.h>
#include<conio.h>
int main()
{
clrscr();
unsigned long first,second,third,n;
first=0; second=1;
cout<<"How many elements(>5)?\n";
cin>>n;
cout<<"Fibonacci series\n";
cout<<first<<" "<<second;
for(int i=2;i<n;++i)
 {
  third=first+second;
  cout<<" "<<third;
  first=second;
  second=third;

 }
getch();
return(0);
}