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:
swallow, heron, crane, flamingo, tackle

Ex Output:
tackle


Ex Input:
dump truck, hoist, crane, ostrich, goose

Ex Output:
dump truck


Ex Input:
hot, there, detailed, fine, probation

Ex Output:

probation