ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
73 lines
1.7 KiB
Markdown
73 lines
1.7 KiB
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
|
|
dashedName: use-bracket-notation-to-find-the-first-character-in-a-string
|
|
---
|
|
|
|
# --description--
|
|
|
|
<dfn>Bracket notation</dfn> is a way to get a character at a specific `index` 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 `var firstName = "Charles"`, you can get the value of the first letter of the string by using `firstName[0]`.
|
|
|
|
Example:
|
|
|
|
```js
|
|
var firstName = "Charles";
|
|
var firstLetter = firstName[0]; // firstLetter is "C"
|
|
```
|
|
|
|
# --instructions--
|
|
|
|
Use bracket notation to find the first character in the `lastName` variable and assign it to `firstLetterOfLastName`.
|
|
|
|
**Hint:** Try looking at the example above if you get stuck.
|
|
|
|
# --hints--
|
|
|
|
The `firstLetterOfLastName` variable should have the value of `L`.
|
|
|
|
```js
|
|
assert(firstLetterOfLastName === 'L');
|
|
```
|
|
|
|
You should use bracket notation.
|
|
|
|
```js
|
|
assert(code.match(/firstLetterOfLastName\s*?=\s*?lastName\[.*?\]/));
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --after-user-code--
|
|
|
|
```js
|
|
(function(v){return v;})(firstLetterOfLastName);
|
|
```
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
// Setup
|
|
var firstLetterOfLastName = "";
|
|
var lastName = "Lovelace";
|
|
|
|
// Only change code below this line
|
|
firstLetterOfLastName = lastName; // Change this line
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
var firstLetterOfLastName = "";
|
|
var lastName = "Lovelace";
|
|
|
|
// Only change code below this line
|
|
firstLetterOfLastName = lastName[0];
|
|
```
|