#include <iostream>
using namespace std;

unsigned long fibonacci(unsigned long);

int main () 
{
   unsigned long result, number;
   
   for(number = 0; number <= 40; number++)
   {
      result = fibonacci(number);
      cout << "Fibonacci(" << number << ") = " << result << endl;
   }
   return 0;
}

//Recursive fibonacci function
/*unsigned long fibonacci(unsigned long n)
{
   if (n==0||n==1)
      return n;
   else
      return fibonacci(n-1) + fibonacci(n-2);
}*/

//Iterative fibonacci function
unsigned long fibonacci(unsigned long n)
{
   static unsigned long int f, f1, f2;
   if (n == 0)
   {
      f1 = 0;
	  f2 = 0;
   }
   else if (n == 1 || n == 2)
   {
      f1 = 1;
	  f2 = 0;
   }
   
   f = f1 + f2;
   f2 = f1;
   f1 = f;

   return f;
}