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:
general, boring, soldier, ubiquitous, average

Ex Output:
soldier


Ex Input:
inlays, concerned, string, notes, fret

Ex Output:
concerned


Ex Input:
solid, sustainability, firm, resistant, inflexible

Ex Output:

sustainability