Double-Ended Queues

Double-Ended Queues

1. Queue-like data structure that supports insertion and deletion at both the front and back of the queue

2. Defined to support the update methods

   • addFirst()
     • Insert an element in front of the deque
   • addLast()
     • Insert an element at the back of the deque
   • removeFirst()
     • Remove and return the first element
   • removeLast()
     • Remove and return the last element

3. Include the accessors

   • first()
   • last()
   • size()
   • isEmpty()