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.

Example Input: mallet, winch, parrot, winch, crane
Example Output: winch

Example Input: level, knockout, deck, fight, gunwale
Example Output: gunwale

Example Input: pie, fritter, doughnut, croquet, goodbye
Example Output:
goodbye