Change the Set<T> class of Display 15.37 so that internally it uses a hash table to store its data instead of a linked list. The headers of the public methods should remain the same so that a program such as the demonstration in Display 15.38 should still work without requiring any changes. Add a constructor that allows the user of the new Set<T> class to specify the size of the hash table array.

For an additional challenge, implement the set using both a hash table and a linked list. Items added to the set should be stored using both data structures. Any operation requiring lookup of an item should use the hash table, and any operation requiring iteration through the items should use the linked list.