Given a set of five words, generate the word from the set that does not belong (i.e. is the least relevant) with the other words. Words are separated by commas.

Ex Input:
corner, ring, crew, deck, apron

Ex Output:
crew


Ex Input:
upraise, crane, excavator, digger, hoist

Ex Output:
hoist


Ex Input:
firm, alignment, tough, ceo, combined

Ex Output:

tough