Hey fellas, I'm stuck on this question.

Question:

Prove that, if S is a set of integers with an upper bound, then $\displaystyle \bar{S}$ has no upper bound.

($\displaystyle \bar{S}$ is the set where x is an integer such that x does not belong to the set S - i.e. everything not in S, I'm guessing)

I would provide an attempt, but I really have no clue. Any ideas?

Thanks a bunch, guys!