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.

Ex Input:
Category: police punishment 
Words: suspension, arrest, classy, custody, fine

Ex Output:
classy


Ex Input:
Category: elements 
Words: pay, cool, combustion, air, fire

Ex Output:
pay


Ex Input:
Category: corporate 
Words: hard, alignment, streamline, ceo, firm

Ex Output:

hard