Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

Input: Consider Input: Category: boats 
Words: head, hull, knockout, deck, dock

Output: knockout


Input: Consider Input: Category: outdoor sport activity 
Words: hiking, climbing, mice, fish, row

Output: mice


Input: Consider Input: Category: military rank 
Words: regular, major, general, soldier, cadet


Output: regular