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circularArrayBuffer

Language/Type: Java Deque
Author: Marty Stepp (on 2013/01/29)

Suppose a deque is implemented using a circular array buffer. Assume that the buffer starts at length 10 and doubles in length when it cannot accommodate an element. Write the state of the deque's internal array at each of the points indicated after the following calls are made. Write 0 in any "empty" slots of the buffer. It may help you to also think about the state from the client's perspective (what would be returned by toString). 

Deque<Integer> deque = new ArrayDeque<Integer>();
deque.addLast(10); deque.addLast(20); deque.addLast(30); deque.addLast(40); deque.addLast(50); // Point A ------->
deque.removeFirst(); deque.removeFirst(); deque.removeFirst(); // Point B ------->
deque.addLast(60); deque.addFirst(70); deque.addFirst(80); // Point C ------->
deque.addFirst(90); deque.addFirst(100); deque.addFirst(200); // Point D ------->
for (int i = 1; i != 7; i++) { deque.removeFirst(); deque.addLast(i); } // Point E ------->
deque.addLast(300); deque.addLast(400); deque.addLast(500); deque.addLast(600); deque.addFirst(700); deque.addFirst(800); // Point F ------->

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