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: elements 
Words: fire, retire, ice, air, earth

Ex Output:
retire


Ex Input:
Category: direction 
Words: down, backward, up, downward, shameful

Ex Output:
shameful


Ex Input:
Category: outdoor sport activity 
Words: hunt, fish, swim, raft, dog

Ex Output:

dog