Master the JavaScript interview with expertly curated questions and solutions. Strategies developed by FAANG engineers help you prep faster, boost confidence, and refine your problem-solving skills.

Master the JavaScript interview by practicing 20 carefully curated interview questions and solutions. These problems will provide the tools you need to tackle any question you find in an interview. Allow ~1 hour per question.

Most questions have multiple solutions presented. All solutions are thoroughly explained and time and space complexity are discussed. A passing familiarity with these ideas is expected. You'll learn how to tackle different types of problems so you can proceed with confidence in your interviews.

These questions go beyond the common problems that we've all seen. FizzBuzz and bubble sort? We start past those.

We'll discuss how to refine algorithms. We'll go over clever, advanced ways of manipulating data that interviewers are looking for. You'll walk away more skilled and confident in your problem solving and interviewing abilities.

This course is taught in ES2015.

Master the JavaScript Interview

# Creating a Queue with O(1) Operations

## NOTE

For this problem, familiarity with queues, hash tables, and linked lists would help.

## Instructions

Create a queue data structure with `O(1)` insertion, deletion, and size calculation.

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# Queue

A [queue](https://en.wikipedia.org/wiki/Queue_(abstract_data_type)) is a data structure that keeps track of data in the order in which it was entered. Items are inserted into the back of the queue and removed from the front of the queue.

A real-world analogy would be a line at a grocery store. Everyone enters the line at the back. The first person who enters will be the first person served.

Common operations available to perform on a queue are:

- `enqueue`, or adding someone to the back of the queue
- `dequeue`, or removing someone from the front of the queue
- `size`, or checking the number of items in the queue

A common interview question is to create a queue that can perform each of these operations in constant-time. There are two common ways to do this.

Feel free to try it yourself first. There are many correct ways to complete this, so we won't have prepared tests for it.

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Learn how to create a queue with constant-time enqueue and dequeue operations.

Introduction

Strings & Arrays

Advanced Strings & Arrays

Algorithms & Data Structures

JavaScript Mastery

Conclusion

Creating a Queue with O(1) Operations

Creating a Queue with O(1) Operations

NOTE

Instructions

Queue