ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
84 lines
1.3 KiB
Markdown
84 lines
1.3 KiB
Markdown
---
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id: 5900f3711000cf542c50fe84
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title: 'Problem 5: Smallest multiple'
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challengeType: 5
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forumTopicId: 302160
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dashedName: problem-5-smallest-multiple
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---
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# --description--
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2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
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What is the smallest positive number that is evenly divisible by all of the numbers from 1 to `n`?
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# --hints--
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`smallestMult(5)` should return a number.
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```js
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assert(typeof smallestMult(5) === 'number');
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```
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`smallestMult(5)` should return 60.
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```js
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assert.strictEqual(smallestMult(5), 60);
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```
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`smallestMult(7)` should return 420.
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```js
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assert.strictEqual(smallestMult(7), 420);
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```
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`smallestMult(10)` should return 2520.
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```js
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assert.strictEqual(smallestMult(10), 2520);
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```
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`smallestMult(13)` should return 360360.
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```js
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assert.strictEqual(smallestMult(13), 360360);
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```
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`smallestMult(20)` should return 232792560.
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```js
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assert.strictEqual(smallestMult(20), 232792560);
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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 smallestMult(n) {
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return true;
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}
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smallestMult(20);
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```
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# --solutions--
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```js
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function smallestMult(n){
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function gcd(a, b) {
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return b === 0 ? a : gcd(b, a%b); // Euclidean algorithm
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}
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function lcm(a, b) {
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return a * b / gcd(a, b);
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}
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var result = 1;
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for(var i = 2; i <= n; i++) {
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result = lcm(result, i);
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}
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return result;
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}
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```
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