#### Overview of this book

Choosing the right data structure is pivotal to optimizing the performance and scalability of applications. This new edition of Hands-On Data Structures and Algorithms with Python will expand your understanding of key structures, including stacks, queues, and lists, and also show you how to apply priority queues and heaps in applications. You’ll learn how to analyze and compare Python algorithms, and understand which algorithms should be used for a problem based on running time and computational complexity. You will also become confident organizing your code in a manageable, consistent, and scalable way, which will boost your productivity as a Python developer. By the end of this Python book, you’ll be able to manipulate the most important data structures and algorithms to more efficiently store, organize, and access data in your applications.
Preface
Free Chapter
Python Data Types and Structures
Introduction to Algorithm Design
Algorithm Design Techniques and Strategies
Stacks and Queues
Trees
Heaps and Priority Queues
Hash Tables
Graphs and Algorithms
Searching
Sorting
Selection Algorithms
String Matching Algorithms
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Index

# Queues

Another important data structure is the queue, which is used to store data similarly to stacks and linked lists, with some constraints and in a specific order. The queue data structure is very similar to the regular queue you are accustomed to in real life. It is just like a line of people waiting to be served in sequential order at a shop. Queues are a fundamentally important concept to grasp since many other data structures are built on them.

A queue works as follows. The first person to join the queue usually gets served first, and everyone will be served in the order in which they joined the queue. The acronym FIFO best explains the concept of a queue. FIFO stands for first in, first out. When people are standing in a queue waiting for their turn to be served, service is only rendered at the front of the queue. Therefore, people are dequeued from the front of the queue and enqueued from the back where they wait their turn. The only time people exit the queue is when...