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: swallow, heron, crane, flamingo, tackle
Example Output: tackle

Example Input: hunting, fish, kayak, goat, raft
Example Output: goat

Example Input: relaxed, firstrate, probation, wispy, fine
Example Output:
relaxed