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: social gathering 
Words: club, group, meeting, grilled cheese, convention

Ex Output:
grilled cheese


Ex Input:
Category: mode of transportation 
Words: spider, fly, drive, train, soar

Ex Output:
spider


Ex Input:
Category: bird 
Words: crane, goose, hummingbird, davit, steam roller

Ex Output:

steam roller