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:
deck, crew, fight, knockout, tko

Ex Output:
crew

Ex Input:
falsification, fib, invent, fudge, cupcake

Ex Output:
cupcake

Ex Input:
up to the moment, detests, current, main, history

Ex Output:
main