I got this question over email and thought it would be good to post here.  When you print your Set, you should NOT print the null values that are beyond the current size of the set.  These empty spaces in the set are considered "out of bounds" and should not be displayed to the user (client) of the Set class.  Consider an ArrayList.  When you use ArrayList there are many null values at the end of the internal array, but these are never displayed when you print an ArrayList because externally those positions do not exist (even though they do internally).

~Keenan Knaur