79d9012432
* fix(curriculum): tests quotes * fix(curriculum): fill seed-teardown * fix(curriculum): fix tests and remove unneeded seed-teardown
76 lines
2.0 KiB
Markdown
76 lines
2.0 KiB
Markdown
---
|
|
id: 5900f37f1000cf542c50fe92
|
|
challengeType: 5
|
|
title: 'Problem 19: Counting Sundays'
|
|
---
|
|
|
|
## Description
|
|
<section id='description'>
|
|
You are given the following information, but you may prefer to do some research for yourself.
|
|
<ul><li>1 Jan 1900 was a Monday.</li><li>Thirty days has September,<br>April, June and November.<br>All the rest have thirty-one,<br>Saving February alone,<br>Which has twenty-eight, rain or shine.<br>And on leap years, twenty-nine.</li><li>A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400.</li>
|
|
How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?
|
|
</section>
|
|
|
|
## Instructions
|
|
<section id='instructions'>
|
|
|
|
</section>
|
|
|
|
## Tests
|
|
<section id='tests'>
|
|
|
|
```yml
|
|
tests:
|
|
- text: <code>countingSundays(1943, 1946)</code> should return 6.
|
|
testString: assert.strictEqual(countingSundays(1943, 1946), 6, '<code>countingSundays(1943, 1946)</code> should return 6.');
|
|
- text: <code>countingSundays(1995, 2000)</code> should return 10.
|
|
testString: assert.strictEqual(countingSundays(1995, 2000), 10, '<code>countingSundays(1995, 2000)</code> should return 10.');
|
|
- text: <code>countingSundays(1901, 2000)</code> should return 171.
|
|
testString: assert.strictEqual(countingSundays(1901, 2000), 171, '<code>countingSundays(1901, 2000)</code> should return 171.');
|
|
|
|
```
|
|
|
|
</section>
|
|
|
|
## Challenge Seed
|
|
<section id='challengeSeed'>
|
|
|
|
<div id='js-seed'>
|
|
|
|
```js
|
|
function countingSundays(firstYear, lastYear) {
|
|
// Good luck!
|
|
return true;
|
|
}
|
|
|
|
countingSundays(1943, 1946);
|
|
```
|
|
|
|
</div>
|
|
|
|
|
|
|
|
</section>
|
|
|
|
## Solution
|
|
<section id='solution'>
|
|
|
|
|
|
```js
|
|
function countingSundays(firstYear, lastYear) {
|
|
let sundays = 0;
|
|
|
|
for (let year = firstYear; year <= lastYear; year++) {
|
|
for (let month = 0; month <= 11; month++) {
|
|
const thisDate = new Date(year, month, 1);
|
|
if (thisDate.getDay() === 0) {
|
|
sundays++;
|
|
}
|
|
}
|
|
}
|
|
return sundays;
|
|
}
|
|
```
|
|
|
|
</section>
|