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:
fair, even, milky, ghostly, luke

Ex Output:
luke


Ex Input:
grasshopper, fly, walk, bus, eagle

Ex Output:
bus


Ex Input:
firm, leverage, rough, inflexible, taut

Ex Output:

leverage