Chapter 6 Stacks, Queues, and Deques On Page 248, Section 6.3.1, implement the Deque Abstract Data Type. That means implementing all the 8 functions and run your codes on Example 6.5 on Page 249. Your program should print out that table in Example 6.5.

6.3.1 The Deque Abstract Data Type The deque abstract data type is richer than both the stack and the queue ADTs. To provide a symmetrical abstraction, the deque ADT is defined to support the following update methods: addFirst (e) : Insert a new element e at the front of the deque. addLast (e) : Insert a new element e at the back of the deque. removeFirst( ): Remove and return the first element of the deque (or null if the deque is empty). removeLast ( ): Remove and return the last element of the deque (or null if the deque is empty). Additionally, the deque ADT will include the following accessors: first( ): Returns the first element of the deque, without removing it (or null if the deque is empty). last ( ): Returns the last element of the deque, without removing it (or null if the deque is empty). size( ): Returns the number of elements in the deque. isEmpty( ): Returns a boolean indicating whether the deque is empty. Example 6.5: The following table shows a series of operations and their effects on an initially empty deque D of integers