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

Removing elements


So far, you have learned how to add elements in the array. Let's take a look at how we can remove a value from an array.

Removing an element from the end of the array

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

numbers.pop(); 

Note

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 the first position

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

for (let 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...