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: employment activity 
Words: recruit, replace, sack, heat, fire

Ex Output:
heat


Ex Input:
Category: type of sandwich 
Words: open-faced, hero, club, discothek, hamburger

Ex Output:
discothek


Ex Input:
Category: poker 
Words: head, draw, deck, chips, joker

Ex Output:

head