Queue Data Structure

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.
• It is used as a buffer in computer systems where we have speed mismatch between two devices that communicate with each other. For example, CPU and keyboard and two devices in a network
• Queue is also used in Operating System algorithms like CPU Scheduling and Memory Management, and many standard algorithms like Breadth First Search of Graph, Level Order Traversal of a Tree.

Basics

• Introduction
• Applications
• Basic Operations
• Array Implementations
• Linked List Implementation

Implementations in Different Languages

• Queue in C++ STL
• Queue In Java
• Queue In Python
• Queue In C#
• Queue in JavaScript
• Queue in Go Language
• Queue in Scala

Easy Problems

• Stack using Queues
• Queue using Stacks
• Level Order Traversal
• BFS for a Graph
• FIFO Page Replacement

Medium Problems

• K Queues in an array
• Reverse a Queue
• First non-repeating in a stream
• Min Knight steps for target

Hard Problems

• Reverse First K of Queue
• Sliding Window Maximum
• Shortest path in a Binary Maze
• Generate Binary from 1 to n
• Maximum Cost Path
• Snake and Ladder Problem
• Shortest safe route
• All possible walks with K edges
• Minimum Cost Path
• Min Cost Path via intermediates

Quick Links:

• ‘Practice Problems’ on Queue
• ‘Quizzes’ on Queue
• Queue Interview Questions
• DSA Tutorial