Book Image

Learning JavaScript Data Structures and Algorithms - Third Edition

Book Image

Learning JavaScript Data Structures and Algorithms - Third Edition

Overview of this book

A data structure is a particular way of organizing data in a computer to utilize resources efficiently. Data structures and algorithms are the base of every solution to any programming problem. With this book, you will learn to write complex and powerful code using the latest ES 2017 features. Learning JavaScript Data Structures and Algorithms begins by covering the basics of JavaScript and introduces you to ECMAScript 2017, before gradually moving on to the most important data structures such as arrays, queues, stacks, and linked lists. You will gain in-depth knowledge of how hash tables and set data structures function as well as how trees and hash maps can be used to search files in an HD or represent a database. This book serves as a route to take you deeper into JavaScript. You’ll also get a greater understanding of why and how graphs, one of the most complex data structures, are largely used in GPS navigation systems in social networks. Toward the end of the book, you’ll discover how all the theories presented in this book can be applied to solve real-world problems while working on your own computer networks and Facebook searches.
Table of Contents (22 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Creating the StackLinkedList class


We can also use the LinkedList class and its variations as internal data structures to create other data structures such as stack, queue, and deque. In this topic, we will learn how to create the stack data structure (covered in Chapter 4, Stacks).

The StackLinkedList class structure and the methods push and pop are declared as follows:

class StackLinkedList {
  constructor() {
    this.items = new DoublyLinkedList(); // {1}
  }
  push(element) {
    this.items.push(element); // {2}
  }
  pop() {
    if (this.isEmpty()) {
      return undefined;
    }
    return this.items.removeAt(this.size() - 1); // {3}
  }
}

For the StackLinkedList class, instead of using an array or a JavaScript object to store the items, we will use a DoublyLinkedList ({1}). The reason for using the doubly linked list instead of the linked list is that for the stack, we will be inserting elements at the end of the list ({2}) and also removing elements from the end of the list ({3})....