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:
emotional state, opposite of up, unhappy, down, miserable

Ex Output:
opposite of up


Ex Input:
answer calls, image, organize, file, correspondence

Ex Output:
image


Ex Input:
heron, tackle, mallet, egret, crane

Ex Output:

tackle