Solve: CircularQueue Poll

Created By: Chris Taylor

/ Version: 2023.8.0

Implement the CircularQueue class that extends the AbstractCircularQueue class and implement the Object poll() method.

The following attributes are available from the AbstractCircularQueue class:

• Object[] items - It's length determines the capacity of the queue. You may assume it is not null
• boolean isEmpty - true when queue is empty
• int frontIndex - index to the front of the queue
• int backIndex - index to the back of the queue