freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/use-bracket-notation-to-find-the-first-character-in-a-string.english.md
Randell Dawson e0e6334628
fix(curriculum): Consolidated comments for JavaScript Algorithms and Data Structures challenges - part 3 of 4 (#38264)
* fix: remove example code from challenge seed

* fix: remove declaration from solution

* fix: added sum variable back in

* fix: reverted description back to original version

* fix: added examples to description section

* fix: added complete sentence

Co-Authored-By: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

* fix: corrected typo

Co-Authored-By: Manish Giri <manish.giri.me@gmail.com>

* fix: reverted to original desc with formatted code

* fix: removed unnecessary code example from description section

Co-Authored-By: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

* fix: failiing test on iterate through array with for loop

* fix: changed to Only change this line

Co-Authored-By: Manish Giri <manish.giri.me@gmail.com>

Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
Co-authored-by: Manish Giri <manish.giri.me@gmail.com>
Co-authored-by: moT01 <tmondloch01@gmail.com>
2020-03-25 16:07:13 +01:00

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Markdown

---
id: bd7123c9c549eddfaeb5bdef
title: Use Bracket Notation to Find the First Character in a String
challengeType: 1
videoUrl: 'https://scrimba.com/c/ca8JwhW'
forumTopicId: 18341
---
## Description
<section id='description'>
<dfn>Bracket notation</dfn> is a way to get a character at a specific <code>index</code> within a string.
Most modern programming languages, like JavaScript, don't start counting at 1 like humans do. They start at 0. This is referred to as <dfn>Zero-based</dfn> indexing.
For example, the character at index 0 in the word "Charles" is "C". So if <code>var firstName = "Charles"</code>, you can get the value of the first letter of the string by using <code>firstName[0]</code>.
Example:
```js
var firstName = "Charles";
var firstLetter = firstName[0]; // firstLetter is "C"
```
</section>
## Instructions
<section id='instructions'>
Use bracket notation to find the first character in the <code>lastName</code> variable and assign it to <code>firstLetterOfLastName</code>.
<strong>Hint: </strong> Try looking at the example above if you get stuck.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: The <code>firstLetterOfLastName</code> variable should have the value of <code>L</code>.
testString: assert(firstLetterOfLastName === 'L');
- text: You should use bracket notation.
testString: assert(code.match(/firstLetterOfLastName\s*?=\s*?lastName\[.*?\]/));
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Setup
var firstLetterOfLastName = "";
var lastName = "Lovelace";
// Only change code below this line
firstLetterOfLastName = lastName; // Change this line
```
</div>
### After Test
<div id='js-teardown'>
```js
(function(v){return v;})(firstLetterOfLastName);
```
</div>
</section>
## Solution
<section id='solution'>
```js
var firstLetterOfLastName = "";
var lastName = "Lovelace";
// Only change code below this line
firstLetterOfLastName = lastName[0];
```
</section>