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:
fearful, content, substance, program, thing

Ex Output:
fearful


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

Ex Output:
bus


Ex Input:
signal, timely, brine, flow, current

Ex Output:

timely