409c39abf1
* feat(curriculum): Add Basic JS Scrimba links * Fix: Add missing video url. * fix: update videoUrl
80 lines
1.9 KiB
Markdown
80 lines
1.9 KiB
Markdown
---
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id: bd7123c9c452eddfaeb5bdef
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title: Use Bracket Notation to Find the Nth-to-Last Character in a String
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cw4vkh9'
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---
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## Description
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<section id='description'>
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You can use the same principle we just used to retrieve the last character in a string to retrieve the Nth-to-last character.
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For example, you can get the value of the third-to-last letter of the <code>var firstName = "Charles"</code> string by using <code>firstName[firstName.length - 3]</code>
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</section>
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## Instructions
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<section id='instructions'>
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Use <dfn>bracket notation</dfn> to find the second-to-last character in the <code>lastName</code> string.
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<strong>Hint</strong><br>Try looking at the <code>thirdToLastLetterOfFirstName</code> variable declaration if you get stuck.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>secondToLastLetterOfLastName</code> should be "c".
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testString: assert(secondToLastLetterOfLastName === 'c', '<code>secondToLastLetterOfLastName</code> should be "c".');
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- text: You have to use <code>.length</code> to get the second last letter.
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testString: assert(code.match(/\.length/g).length === 2, 'You have to use <code>.length</code> to get the second last letter.');
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Example
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var firstName = "Ada";
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var thirdToLastLetterOfFirstName = firstName[firstName.length - 3];
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// Setup
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var lastName = "Lovelace";
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// Only change code below this line
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var secondToLastLetterOfLastName = lastName;
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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(function(v){return v;})(secondToLastLetterOfLastName);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var firstName = "Ada";
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var thirdToLastLetterOfFirstName = firstName[firstName.length - 3];
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var lastName = "Lovelace";
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var secondToLastLetterOfLastName = lastName[lastName.length - 2];
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```
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</section>
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