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: chocolate food 
Words: cake, fudge, rich, invent, cream

Ex Output:
invent


Ex Input:
Category: social gathering 
Words: club, bar, dance hall, discothek, roll

Ex Output:
roll


Ex Input:
Category: police punishment 
Words: detailed, hearing, suspension, fine, custody

Ex Output:

detailed