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Learning JavaScript Data Structures and Algorithms - Third Edition
book

Learning JavaScript Data Structures and Algorithms - Third Edition

by Loiane Avancini
April 2018
Beginner to intermediate content levelBeginner to intermediate
426 pages
10h 19m
English
Packt Publishing
Content preview from Learning JavaScript Data Structures and Algorithms - Third Edition

The size method

The next method we will implement is the size method (which returns how many elements are in the set). There are three ways of implementing this method.

The first method is to use a length variable and control it whenever we use the add or remove method, as we used in the LinkedList, Stack, and Queue classes in the previous chapters.

In the second method, we use a built-in method from the Object class in JavaScript (ECMAScript 2015+), as follows:

size() { 
  return Object.keys(this.items).length; // {1} 
}; 

The Object class in JavaScript contains a method called keys that returns an array of all the properties of a given object. In this case, we can use the length property of this array ({1}) to return how many properties we ...

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Learning JavaScript Data Structures and Algorithms

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Publisher Resources

ISBN: 9781788623872Supplemental Content