Design, implement, and test a soubly linked list ADT, using DLLNode objects as the nodes. In additio

Design, implement, and test a soubly linked list ADT, using DLLNode objects as the nodes. In addition to our standard list operations, your class should provide for backward iteration through the list. To support this operation , it should export a resetBack method and a getPrevious method. To facilate this, you may want to include an instance variable last than always re ferences the last element on the list