2018-09-30 23:01:58 +01:00
										 
									 
								 
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								id: 5900f3731000cf542c50fe86
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								title: 'Problem 7: 10001st prime'
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								challengeType: 5
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 302182
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: problem-7-10001st-prime
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								---
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								# --description--
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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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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											2020-02-28 21:39:47 +09:00
										 
									 
								 
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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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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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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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											2020-09-15 09:57:40 -07:00
										 
									 
								 
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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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