1. Consider the Map ADT from Section 3.2:
(a) Provide a new implementation that uses a sorted doubly linked list and includes a probe reference for the search operations.
(b) Modify your Map class to include an iterator for use with a for loop.
2. A MultiMap ADT is similar to the Map ADT but it uses two keys that map to a single data item instead of a single key as used with the Map ADT. Define and implement a MultiMap ADT.