90 lines
3.1 KiB
Markdown
90 lines
3.1 KiB
Markdown
---
|
|
id: 587d825b367417b2b2512c8e
|
|
title: Create a Hash Table
|
|
challengeType: 1
|
|
videoUrl: ''
|
|
localeTitle: ''
|
|
---
|
|
|
|
## Description
|
|
undefined
|
|
|
|
## Instructions
|
|
undefined
|
|
|
|
## Tests
|
|
<section id='tests'>
|
|
|
|
```yml
|
|
tests:
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; return (typeof test === "object")})(), "The HashTable data structure exists.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; return ((typeof test.add) === "function")})(), "The HashTable has an add method.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; return ((typeof test.remove) === "function")})(), "The HashTable has an remove method.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; return ((typeof test.lookup) === "function")})(), "The HashTable has an lookup method.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; test.add("key", "value"); return (test.lookup("key") === "value")})(), "The add method adds key value pairs and the lookup method returns the values associated with a given key.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; test.add("key", "value"); test.remove("key"); return (test.lookup("key") === null)})(), "The remove method accepts a key as input and removes the associated key value pair.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; called = 0; test.add("key1","value1"); test.add("key2","value2"); test.add("key3","value3"); return (called === 3)})(), "Items are added using the hash function.");'
|
|
- text: ''
|
|
testString: 'assert((function() { var test = false; if (typeof HashTable !== "undefined") { test = new HashTable() }; called = 0; test.add("key1","value1"); test.add("1key","value2"); test.add("ke1y","value3"); return (test.lookup("key1") === "value1" && test.lookup("1key") == "value2" && test.lookup("ke1y") == "value3")})(), "The hash table handles collisions.");'
|
|
|
|
```
|
|
|
|
</section>
|
|
|
|
## Challenge Seed
|
|
<section id='challengeSeed'>
|
|
|
|
<div id='js-seed'>
|
|
|
|
```js
|
|
var called = 0;
|
|
var hash = (string) => {
|
|
called++;
|
|
var hash = 0;
|
|
for (var i = 0; i < string.length; i++) { hash += string.charCodeAt(i); }
|
|
return hash;
|
|
};
|
|
var HashTable = function() {
|
|
this.collection = {};
|
|
// change code below this line
|
|
// change code above this line
|
|
};
|
|
|
|
```
|
|
|
|
</div>
|
|
|
|
### Before Test
|
|
<div id='js-setup'>
|
|
|
|
```js
|
|
var called = 0;
|
|
var hash = (string) => {
|
|
called++;
|
|
var hash = 0;
|
|
for (var i = 0; i < string.length; i++) { hash += string.charCodeAt(i); };
|
|
return hash;
|
|
};
|
|
|
|
```
|
|
|
|
</div>
|
|
|
|
|
|
</section>
|
|
|
|
## Solution
|
|
<section id='solution'>
|
|
|
|
```js
|
|
// solution required
|
|
```
|
|
</section>
|