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:
bored, amp, board, fret, truss rod

Ex Output:
bored


Ex Input:
centimeter, yard, foot, milimeter, head

Ex Output:
head


Ex Input:
general, major, private, average, sargent

Ex Output:

average