86 lines
2.0 KiB
Markdown
86 lines
2.0 KiB
Markdown
|
---
|
||
|
id: 5a23c84252665b21eecc7edc
|
||
|
title: Last Friday of each month
|
||
|
challengeType: 5
|
||
|
forumTopicId: 302299
|
||
|
---
|
||
|
|
||
|
## Description
|
||
|
|
||
|
<section id='description'>
|
||
|
|
||
|
Write a function that returns the date of the last Friday of a given month for a given year.
|
||
|
|
||
|
</section>
|
||
|
|
||
|
## Instructions
|
||
|
|
||
|
<section id='instructions'>
|
||
|
|
||
|
</section>
|
||
|
|
||
|
## Tests
|
||
|
|
||
|
<section id='tests'>
|
||
|
|
||
|
```yml
|
||
|
tests:
|
||
|
- text: <code>lastFriday</code> should be a function.
|
||
|
testString: assert(typeof lastFriday == 'function');
|
||
|
- text: <code>lastFriday(2018, 1)</code> should return a number.
|
||
|
testString: assert(typeof lastFriday(2018, 1) == 'number');
|
||
|
- text: <code>lastFriday(2018, 1)</code> should return <code>26</code>.
|
||
|
testString: assert.equal(lastFriday(2018, 1), 26);
|
||
|
- text: <code>lastFriday(2017, 2)</code> should return <code>24</code>.
|
||
|
testString: assert.equal(lastFriday(2017, 2), 24);
|
||
|
- text: <code>lastFriday(2012, 3)</code> should return <code>30</code>.
|
||
|
testString: assert.equal(lastFriday(2012, 3), 30);
|
||
|
- text: <code>lastFriday(1900, 4)</code> should return <code>27</code>.
|
||
|
testString: assert.equal(lastFriday(1900, 4), 27);
|
||
|
- text: <code>lastFriday(2000, 5)</code> should return <code>26</code>.
|
||
|
testString: assert.equal(lastFriday(2000, 5), 26);
|
||
|
- text: <code>lastFriday(2006, 6)</code> should return <code>30</code>.
|
||
|
testString: assert.equal(lastFriday(2006, 6), 30);
|
||
|
- text: <code>lastFriday(2010, 7)</code> should return <code>30</code>.
|
||
|
testString: assert.equal(lastFriday(2010, 7), 30);
|
||
|
- text: <code>lastFriday(2005, 8)</code> should return <code>26</code>.
|
||
|
testString: assert.equal(lastFriday(2005, 8), 26);
|
||
|
```
|
||
|
|
||
|
</section>
|
||
|
|
||
|
## Challenge Seed
|
||
|
|
||
|
<section id='challengeSeed'>
|
||
|
|
||
|
<div id='js-seed'>
|
||
|
|
||
|
```js
|
||
|
function lastFriday(year, month) {
|
||
|
|
||
|
}
|
||
|
```
|
||
|
|
||
|
</div>
|
||
|
</section>
|
||
|
|
||
|
## Solution
|
||
|
|
||
|
<section id='solution'>
|
||
|
|
||
|
```js
|
||
|
function lastFriday(year, month) {
|
||
|
var i, last_day;
|
||
|
i = 0;
|
||
|
while (true) {
|
||
|
last_day = new Date(year, month, i);
|
||
|
if (last_day.getDay() === 5) {
|
||
|
return last_day.getDate();
|
||
|
}
|
||
|
i -= 1;
|
||
|
}
|
||
|
}
|
||
|
```
|
||
|
|
||
|
</section>
|