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>
87 lines
1.3 KiB
Markdown
87 lines
1.3 KiB
Markdown
---
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id: 5900f3731000cf542c50fe86
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title: 'Problem 7: 10001st prime'
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challengeType: 5
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forumTopicId: 302182
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dashedName: problem-7-10001st-prime
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---
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# --description--
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By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.
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What is the `n`th prime number?
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# --hints--
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`nthPrime(6)` should return a number.
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```js
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assert(typeof nthPrime(6) === 'number');
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```
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`nthPrime(6)` should return 13.
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```js
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assert.strictEqual(nthPrime(6), 13);
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```
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`nthPrime(10)` should return 29.
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```js
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assert.strictEqual(nthPrime(10), 29);
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```
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`nthPrime(100)` should return 541.
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```js
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assert.strictEqual(nthPrime(100), 541);
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```
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`nthPrime(1000)` should return 7919.
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```js
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assert.strictEqual(nthPrime(1000), 7919);
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```
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`nthPrime(10001)` should return 104743.
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```js
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assert.strictEqual(nthPrime(10001), 104743);
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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 nthPrime(n) {
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return true;
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}
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nthPrime(10001);
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```
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# --solutions--
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```js
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const nthPrime = n => {
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let pN = 2;
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let step = 0;
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while (step < n) {
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let isPrime = true;
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let rootN = Math.sqrt(pN);
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for (let i = 2; i <= rootN; i++) {
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if (!(pN % i)) {
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isPrime = false;
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break;
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}
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}
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isPrime ? step++ : '';
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pN++;
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}
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return pN - 1;
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}
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```
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