Book Image

Learning JavaScript Data Structures and Algorithms - Second Edition

By : Loiane Groner
Book Image

Learning JavaScript Data Structures and Algorithms - Second Edition

By: Loiane Groner

Overview of this book

This book begins by covering basics of the JavaScript language and introducing ECMAScript 7, before gradually moving on to the current implementations of ECMAScript 6. You will gain an in-depth knowledge of how hash tables and set data structure functions, as well as how trees and hash maps can be used to search files in a HD or represent a database. This book is an accessible route deeper into JavaScript. Graphs being one of the most complex data structures you’ll encounter, we’ll also give you a better understanding of why and how graphs are largely used in GPS navigation systems in social networks. Toward the end of the book, you’ll discover how all the theories presented by this book can be applied in real-world solutions while working on your own computer networks and Facebook searches.
Table of Contents (18 chapters)
Learning JavaScript Data Structures and Algorithms - Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface

Dictionaries


As you have learned, a set is a collection of distinct elements (nonrepeated elements). A dictionary is used to store [key, value] pairs, where the key is used to find a particular element. A dictionary is very similar to a set; a set stores a [key, key] collection of elements, and a dictionary stores a [key, value] collection of elements. A dictionary is also known as a map.

In this chapter, we will cover some examples of how to use the dictionary data structure in the real world: a dictionary itself (the words and their definitions) and an address book.

Creating a dictionary

Similarly to the Set class, ECMAScript 6 also contains an implementation of the Map class, also known as a dictionary.

The class we will implement in this chapter is based on the Map implementation of ECMAScript 6. You will notice that it is very similar to the Set class (but instead of storing a [key, key] pair, we will store a [key, value] pair).

This is the skeleton of our Dictionary class:

function Dictionary...