Finding the difference between strings in Ruby

Question

I need to take two strings, compare them, and print the difference between them.

So say I have:

teamOne = "Billy, Frankie, Stevie, John"
teamTwo = "Billy, Frankie, Stevie"

$ teamOne.eql? teamTwo 
=> false

I want to say "If the two strings are not equal, print whatever it is that is different between them. In this case, I'm just looking to print "John."

Answer 1

All of the solutions so far ignore the fact that the second array can also have elements that the first array doesn't have. Chuck has pointed out a fix (see comments on other posts), but there is a more elegant solution if you work with sets:

require 'set'

teamOne = "Billy, Frankie, Stevie, John"
teamTwo = "Billy, Frankie, Stevie, Zach"

teamOneSet = teamOne.split(', ').to_set
teamTwoSet = teamTwo.split(', ').to_set

teamOneSet ^ teamTwoSet # => #<Set: {"John", "Zach"}>

This set can then be converted back to an array if need be.