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

Set operations


We can perform the following operations on sets:

  • Union: Given two sets, this returns a new set with elements from both the given sets

  • Intersection: Given two sets, this returns a new set with the elements that exist in both sets

  • Difference: Given two sets, this returns a new set with all the elements that exist in the first set and do not exist in the second set

  • Subset: This confirms whether a given set is a subset of another set

Set union

The mathematic concept of union is: the union of sets A and B, denoted by:

This set is defined as:

This means that x (the element) exists in A or x exists in B. The following diagram exemplifies the union operation:

Now, let's implement the union method in our Set class via the following code:

this.union = function(otherSet){ 
  let unionSet = new Set(); //{1} 
 
  let values = this.values(); //{2} 
  for (let i=0; i<values.length; i++){ 
    unionSet.add(values[i]); 
  } 
 
  values = otherSet.values(); //{3} 
  for (let i=0; i&lt...