/* Copyright 2005 Daniel Cer (daniel.cer@cs.colorado.edu)

This work is licensed under the Creative Commons Attribution-NonCommercial-
ShareAlike License. To view a copy of this license, visit 
http://creativecommons.org/licenses/by-nc-sa/2.5/ or send a letter to 
Creative Commons, 543 Howard Street, 5th Floor, San Francisco, California, 
94105, USA.
*/

#include <stdio.h>

int fibonacci(int n) {
  if (n <= 0) return -1; if (n <= 2) return 1;
  return fibonacci(n-1) + fibonacci(n-2);
}

int main (int argc, char *argv[]) { int n;
  if (argc != 2) { 
    fprintf(stderr, "Usage:\n\t%s (n-th fibonacci # to calculate)\n", argv[0]);
    return -1; 
  } 
  n = atoi(argv[1]);
  printf("fibonacci(%d): %d\n", n, fibonacci(n)); 
  return 0;
}