Given k alphabets and a length of n, find how many unique strings can be formed using these k alphabets of length n. Two strings are considered same if one can be obtained from another through rotation or through reversing.

Can anyone help me provide a critical test case for this problem ?

problem link: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&category=24&problem=4955&mosmsg=Submission+received+with+ID+17444380

my solution: http://ideone.com/JDfL7D