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.

Ex Input:
sergeant, lieutenant, fighter, general, ordinary

Ex Output:
ordinary


Ex Input:
promote, empower, fire, ice, ban

Ex Output:
ice


Ex Input:
file, firewall, motherboard, correspondence, space

Ex Output:

correspondence