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

Removing elements


So far, you have learned how to add values to the end and at the beginning of an array. Let's take a look at how we can remove a value from an array.

To remove a value from the end of an array, we can use the pop method:

numbers.pop(); 

Tip

The push and pop methods allow an array to emulate a basic stack data structure, which is the subject of the next chapter.

The output of our array will be the numbers from -4 to 12. The length of our array is 17.

Removing an element from first position

To remove a value from the beginning of the array, we can use the following code:

for (var i=0; i<numbers.length; i++){ 
  numbers[i] = numbers[i+1]; 
} 

We can represent the previous code using the following diagram:

We shifted all the elements one position to the left. However, the length of the array is still the same (17), meaning we still have an extra element in our array (with an undefined value). The last time the code inside the loop was executed, i+1 was a reference...