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: employment activity 
Words: fire, hire, ground, pay, retire

Output: ground


Input: Consider Input: Category: type of sandwich 
Words: submarine, group, club, roll, grilled cheese

Output: group


Input: Consider Input: Category: accomodation 
Words: apartment, round, valley, flat, even


Output: valley