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.

Input: Consider Input: Category: type of rigidity 
Words: solid, leverage, hard, unbending, firm

Output: leverage


Input: Consider Input: Category: police punishment 
Words: jail, fine, bright, arrest, flyaway

Output: bright


Input: Consider Input: Category: corporate 
Words: common, firm, solid, combined, private


Output: solid