Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

Ex Input:
Category: elements 
Words: ban, fire, combustion, ground, flame

Ex Output:
ban


Ex Input:
Category: type of sandwich 
Words: open-faced, team, roll, doorstep, club

Ex Output:
team


Ex Input:
Category: animal 
Words: tiger, hiking, goat, fish, shark

Ex Output:

hiking