freeCodeCamp/guide/english/certifications/coding-interview-prep/data-structures/create-a-set-class/index.md

title
Create a Set Class

Create a Set Class

Method:

• A Set is an abstract data structure.
• It can store unique value and the collection is unordered.
• In this challenge, we have to implement .add() method. This method should only add unique values to collection.
  • The method should return true, if the value is sucessfully added to the collection, otherwise it should return false.

Solution:

function Set() {
    // the var collection will hold our set
    var collection = [];
    // this method will check for the presence of an element and return true or false
    this.has = function(element) {
        return (collection.indexOf(element) !== -1);
    };
    // this method will return all the values in the set
    this.values = function() {
        return collection;
    };
    this.add = function(el) {
        return this.has(el) ? false : Boolean(collection.push(el));
    }
}

Resources:

• Wikipedia