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: bird 
Words: digger, heron, crane, mallet, sandpiper

Ex Output:
digger


Ex Input:
Category: police punishment 
Words: prime, fine, jail, suspension, well

Ex Output:
well


Ex Input:
Category: type of rigidity 
Words: rigged, stiff, unyielding, firm, llc

Ex Output:

llc