Calculating Execution Time

[gr8flmommy]

I am trying to find the execution time for a program that calculates Fibonacci numbers using an iterative algorithm, but I am getting no data - my output is 0 ms/0 clicks. I copied and pasted this code from another program where it works as it is intended to and calculates execution time for a recursive algorithm. What am I missing?

//Function Prototypes
long int fibI(int);

#include <iostream>
#include <time.h>
#include <ctime>

int main()
{
   int num = 40;                //Number of Fibonacci numbers to genreate

   //Begins iterative clock
   clock_t beginI = clock();
   //Calculates and displays Fibonacci numbers
   std::cout <<  "\nFibonacci Number " << num << ":  " << fibI(num) << std::endl;
   //Stops recursive clock
   clock_t endI = clock();
   //Prints number of clicks for execution
   std::cout << "\nElapsed Time (Iterative): " << ((double(endI-beginI)/CLOCKS_PER_SEC) * 1000) << " ms\n";
   std::cout << "\nClicks:  " << endI << std::endl;
   return 0;
}

/*************************************************
 *              fibI                            *
 *                                              *
 * This function iteratively calculates         *
 * Fibonacci numbers.  Reference:               *
 * www.codeproject.com/tips/109443,             *
 * author julian                                *
 *                                              *
 * Accepts: integer (position of Fibonacci      *
 *          number in series)                   *
 *                                              *
 * Returns: integer (value of specified         *
 *          Fibonacci number)                   *
*************************************************/
long int fibI (int n)
{
   int first = 0;
   int second = 1;
   int counter = 2;

   while (counter < n)
   {
        int temp = second;
        second = first + second;
        first = temp;
        ++counter;
   }

   if (n == 0)
      return 0;

   else
        return (first + second);
}

[ne555]

computers are fast