The main focus of this book is employing data structures and algorithms in real-world web applications using JavaScript.
With JavaScript making its way onto the server side and with Single Page Application (SPA) frameworks taking over the client side, a lot, if not all, of the business logic, is being ported over to the client side. This makes it crucial to employ hand-crafted data structures and algorithms that are tailor-made for a given use case.
For example, when working on data visualizations such as charts, graphs, and 3D or 4D models, there might be tens or even hundreds of thousands of complex objects being served from the server, sometimes in near real time. There are more ways than one in which this data can be handled and that is what we will be exploring, with real-world examples.
This book is for anyone who has an interest in and basic knowledge of HTML, CSS, and JavaScript. We will also be using Node.js, Express, and Angular to create some of the web apps and APIs that leverage our data structures.
Chapter 1, Building Stacks for Application State Management, introduces building and using stacks for things such as a custom back button for an application and a syntax parser and evaluator for an online IDE.
Chapter 2, Creating Queues for In-Order Executions, demonstrates using queues and their variants to create a messaging service capable of handling message failures. Then, we perform a quick comparison of the different types of queues.
Chapter 3, Using Sets and Maps for Faster Applications, use sets, and maps to create keyboard shortcuts to navigate between your application states. Then, we create a custom application tracker for recording the analytics information of a web application. We conclude the chapter with a performance comparison of sets and maps with arrays and objects.
Chapter 4, Using Trees for Faster Lookup and Modifications, leverages tree data structures to form a typeahead component. Then, we create a credit card approval predictor to determine whether or not a credit card application would be accepted based on historical data.
Chapter 5, Simplify Complex Applications Using Graphs, discusses graphs with examples such as creating a reference generator for a job portal and a friend recommendation system on a social media website.
Chapter 6, Exploring Types of Algorithms, explores some of the most important algorithms, such as Dijkstra's, knapsack 1/0, greedy algorithms, and so on.
Chapter 7, Sorting and its Applications, explores merge sort, insertion sort, and quick sort with examples. Then, we run a performance comparison on them.
Chapter 8, Big O notation, Space, and Time Complexity, discusses the notations denoting complexities and then, moves on to discuss what space and time complexities are and how they impact our application.
Chapter 9, Micro-optimizations and Memory Management, explores the best practices for HTML, CSS, JavaScript and then, moves on to discuss some of the internal workings of Google Chrome and how we can leverage it to render our applications better and more quickly.
- Basic knowledge of JavaScript, HTML, and CSS
- Have Node.js installed (https://nodejs.org/en/download/)
- Install WebStorm IDE (https://www.jetbrains.com/webstorm/download) or similar
- A next-generation browser such as Google Chrome (https://www.google.com/chrome/browser/desktop/)
- Familiarity with Angular 2.0 or greater is a plus but is not required
- The screenshots in this book are taken on a macOS. There would be little difference (if any) for users of any other OS. The code samples, however, would run without any discrepancies irrespective of the OS. Anywhere we have
CMD/cmd/commandspecified, please useCTRL/ctrl/controlkey on the windows counterpart. If you seereturn, please use Enter and if you see the termterminal/Terminalplease use its equivalentcommand prompton windows. - In this book, the code base is built incrementally as the topic progresses. So, when you compare the beginning of a code sample with the code base in GitHub, be aware that the GitHub code is the final form of the topic or the example that you are referring to.
You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.
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We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here:https://www.packtpub.com/sites/default/files/downloads/HandsOnDataStructuresandAlgorithmswithJavaScript_ColorImages.pdf.
There are a number of text conventions used throughout this book.
CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The native array operations have varying time complexities. Let's take Array.prototype.splice and Array.prototype.push."
A block of code is set as follows:
class Stack {
constructor() {
}
}When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:
var express = require('express');
var app = express();
var data = require('./books.json');
var Insertion = require('./sort/insertion');Any command-line input or output is written as follows:
ng new back-buttonBold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "When the user clicks on the back button, we will navigate to the previous state of the application from the stack."
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