2019-03-21 11:52:35 +05:30
										 
									 
								 
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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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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 302299
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: last-friday-of-each-month
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											2019-03-21 11:52:35 +05:30
										 
									 
								 
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								# --description--
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											2019-07-18 17:32:12 +02:00
										 
									 
								 
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											2019-03-21 11:52:35 +05:30
										 
									 
								 
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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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											2020-03-30 11:23:18 -05:00
										 
									 
								 
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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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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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								`lastFriday(2018, 1)` should return a number.
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											2019-03-21 11:52:35 +05:30
										 
									 
								 
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								```js
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								assert(typeof lastFriday(2018, 1) == 'number');
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								```
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											2020-03-30 11:23:18 -05:00
										 
									 
								 
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								`lastFriday(2018, 1)` should return `26`.
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											2019-07-18 17:32:12 +02:00
										 
									 
								 
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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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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											2019-03-21 11:52:35 +05:30
										 
									 
								 
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								```js
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								assert.equal(lastFriday(2017, 2), 24);
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								```
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											2020-09-15 09:57:40 -07:00
										 
									 
								 
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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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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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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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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											2020-03-30 11:23:18 -05:00
										 
									 
								 
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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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