freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/data-structures/remove-from-a-set.english.md

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---
id: 587d8253367417b2b2512c6b
title: Remove from a Set
challengeType: 1
---
## Description
<section id='description'>
In this exercises we are going to create a delete function for our set. The function should be named <code>this.remove</code>. This function should accept a value and check if it exists in the set. If it does, remove that value from the set, and return true. Otherwise, return false.
</section>
## Instructions
<section id='instructions'>
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: Your <code>Set</code> class should have a <code>remove</code> method.
testString: assert((function(){var test = new Set(); return (typeof test.remove === 'function')}()), 'Your <code>Set</code> class should have a <code>remove</code> method.');
- text: Your <code>remove</code> method should only remove items that are present in the set.
testString: assert.deepEqual((function(){var test = new Set(); test.add('a');test.add('b');test.remove('c'); return test.values(); })(), ['a', 'b'], 'Your <code>remove</code> method should only remove items that are present in the set.');
- text: Your <code>remove</code> method should remove the given item from the set.
testString: assert((function(){var test = new Set(); test.add('a');test.add('b');test.remove('a'); var vals = test.values(); return (vals[0] === 'b' && vals.length === 1)}()), 'Your <code>remove</code> method should remove the given item from the set.');
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
function Set() {
// the var collection will hold the 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 method will add an element to the set
this.add = function(element) {
if(!this.has(element)){
collection.push(element);
return true;
}
return false;
};
// change code below this line
// change code above this line
}
```
</div>
</section>
## Solution
<section id='solution'>
```js
function Set() {var collection = []; this.has = function(e){return(collection.indexOf(e) !== -1);};this.values = function() {return collection;};this.add = function(element) {if (!this.has(element)) {collection.push(element);return true;} else {return false;}};this.remove = function(element) {if(this.has(element)) {var i = collection.indexOf(element);collection.splice(i, 1);return true;}return false;};}
```
</section>