100 lines
1.5 KiB
Markdown
100 lines
1.5 KiB
Markdown
![]() |
---
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id: 5a23c84252665b21eecc7edc
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title: Last Friday of each month
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challengeType: 5
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forumTopicId: 302299
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dashedName: last-friday-of-each-month
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---
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# --description--
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Write a function that returns the date of the last Friday of a given month for a given year.
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# --hints--
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`lastFriday` should be a function.
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```js
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assert(typeof lastFriday == 'function');
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```
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`lastFriday(2018, 1)` should return a number.
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```js
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assert(typeof lastFriday(2018, 1) == 'number');
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```
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`lastFriday(2018, 1)` should return `26`.
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```js
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assert.equal(lastFriday(2018, 1), 26);
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```
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`lastFriday(2017, 2)` should return `24`.
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```js
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assert.equal(lastFriday(2017, 2), 24);
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```
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`lastFriday(2012, 3)` should return `30`.
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```js
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assert.equal(lastFriday(2012, 3), 30);
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```
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`lastFriday(1900, 4)` should return `27`.
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```js
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assert.equal(lastFriday(1900, 4), 27);
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```
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`lastFriday(2000, 5)` should return `26`.
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```js
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assert.equal(lastFriday(2000, 5), 26);
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```
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`lastFriday(2006, 6)` should return `30`.
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```js
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assert.equal(lastFriday(2006, 6), 30);
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```
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`lastFriday(2010, 7)` should return `30`.
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```js
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assert.equal(lastFriday(2010, 7), 30);
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```
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`lastFriday(2005, 8)` should return `26`.
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```js
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assert.equal(lastFriday(2005, 8), 26);
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```
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# --seed--
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## --seed-contents--
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```js
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function lastFriday(year, month) {
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}
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```
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# --solutions--
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```js
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function lastFriday(year, month) {
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var i, last_day;
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i = 0;
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while (true) {
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last_day = new Date(year, month, i);
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if (last_day.getDay() === 5) {
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return last_day.getDate();
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}
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i -= 1;
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}
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}
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```
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