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:
file, keys, document, fax, ram

Ex Output:
fax


Ex Input:
fly, glide, flutter, eagle, train

Ex Output:
eagle


Ex Input:
well, honorable, fair, just, brisk

Ex Output:

brisk