Data Structures: Queue

A Queue is a FIFO (First In First Out — the element placed at first can be accessed at first) structure which can be commonly found in many programming languages. This structure is named as “queue” because it resembles a real-world queue — people waiting in a queue (line).

Just like in like real life, the person who was in line first gets served first.

Diagram: Queue

Queue Operations

Given below are the 2 basic operations that can be performed on a queue. Reference the diagram above

  • Enqueue: Insert an element to the end of the queue.
  • Dequeue: Delete the element from the beginning of the queue.

Applications of Queues

  • Used to manage threads in multithreading.
  • Used to implement queuing systems (e.g.: priority queues).