6cfd0fc503
* fix: improve Project Euler descriptions and test case Improve formatting of Project Euler test descriptions. Also add poker hands array and new test case for problem 54 * feat: add typeof tests and gave functions proper names for first 100 challenges * fix: continue fixing test descriptions and adding "before test" sections * fix: address review comments * fix: adjust grids in 18 and 67 and fix some text that reference files rather than the given arrays * fix: implement bug fixes and improvements from review * fix: remove console.log statements from seed and solution
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id, challengeType, title, forumTopicId
| id | challengeType | title | forumTopicId |
|---|---|---|---|
| 5900f37f1000cf542c50fe92 | 5 | Problem 19: Counting Sundays | 301827 |
Description
You are given the following information, but you may prefer to do some research for yourself.
- 1 Jan 1900 was a Monday.
- Thirty days has September,
April, June and November.
All the rest have thirty-one,
Saving February alone,
Which has twenty-eight, rain or shine.
And on leap years, twenty-nine. - A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400.
How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?
Instructions
Tests
tests:
- text: <code>countingSundays(1943, 1946)</code> should return a number.
testString: assert(typeof countingSundays(1943, 1946) === 'number');
- text: <code>countingSundays(1943, 1946)</code> should return 6.
testString: assert.strictEqual(countingSundays(1943, 1946), 6);
- text: <code>countingSundays(1995, 2000)</code> should return 10.
testString: assert.strictEqual(countingSundays(1995, 2000), 10);
- text: <code>countingSundays(1901, 2000)</code> should return 171.
testString: assert.strictEqual(countingSundays(1901, 2000), 171);
Challenge Seed
function countingSundays(firstYear, lastYear) {
// Good luck!
return true;
}
countingSundays(1943, 1946);
Solution
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;
}