Queue Data Structure

Last Updated : 30 Jul, 2024
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A Queue Data Structure is a fundamental concept in computer science used for storing and managing data in a specific order. It follows the principle of “First in, First out” (FIFO), where the first element added to the queue is the first one to be removed. Queues are commonly used in various algorithms and applications for their simplicity and efficiency in managing data flow.

Queue Data Structure

Table of Content

What is Queue in Data Structures?

A queue is a linear data structure that follows the First-In-First-Out (FIFO) principle. It operates like a line where elements are added at one end (rear) and removed from the other end (front).

Basic Operations of Queue Data Structure

  • Enqueue (Insert): Adds an element to the rear of the queue.
  • Dequeue (Delete): Removes and returns the element from the front of the queue.
  • Peek: Returns the element at the front of the queue without removing it.
  • Empty: Checks if the queue is empty.
  • Full: Checks if the queue is full.

Applications of Queue

  • Task scheduling in operating systems
  • Data transfer in network communication
  • Simulation of real-world systems (e.g., waiting lines)
  • Priority queues for event processing queues for event processing

Implementation of Queues

Queues can be implemented using Two techniques:

Basics of Queue Data Structure

Implementations of Queue in various Programming Languages

Other Implementations of Queue Data Structure

Easy Problems on Queue Data Structure

Medium Problems on Queue Data Structure

Hard Problems on Queue Data Structure

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