Fibbosum (SPOJ) - why wrong answer, ran 50 test cases

WHY IS MY CODE FOR FIBBOSUM ([PROBLEM][1]) IS SHOWING WRONG ANSWER LIKE MAN I RAN IT ON 50 TEST CASES AND IT WORKS PERFECTLY FINE

HERE IS MY CODE


[2]


  [1]: https://www.spoj.com/problems/FIBOSUM/
  [2]: https://ideone.com/ws6vSu

well i spotted out the error. will be happy to tell if anyone asks the error