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							|  |  |  | id: 5900f3731000cf542c50fe86 | 
					
						
							|  |  |  | challengeType: 5 | 
					
						
							|  |  |  | title: 'Problem 7: 10001st prime' | 
					
						
							|  |  |  | --- | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. | 
					
						
							|  |  |  | What is the <code>n</code>th prime number? | 
					
						
							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Instructions
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							|  |  |  | <section id='instructions'> | 
					
						
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							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Tests
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							|  |  |  | <section id='tests'> | 
					
						
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							|  |  |  | ```yml | 
					
						
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										 |  |  | tests: | 
					
						
							|  |  |  |   - text: <code>nthPrime(6)</code> should return 13. | 
					
						
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										 |  |  |     testString: assert.strictEqual(nthPrime(6), 13, '<code>nthPrime(6)</code> should return 13.'); | 
					
						
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										 |  |  |   - text: <code>nthPrime(10)</code> should return 29. | 
					
						
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										 |  |  |     testString: assert.strictEqual(nthPrime(10), 29, '<code>nthPrime(10)</code> should return 29.'); | 
					
						
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										 |  |  |   - text: <code>nthPrime(100)</code> should return 541. | 
					
						
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										 |  |  |     testString: assert.strictEqual(nthPrime(100), 541, '<code>nthPrime(100)</code> should return 541.'); | 
					
						
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										 |  |  |   - text: <code>nthPrime(1000)</code> should return 7919. | 
					
						
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										 |  |  |     testString: assert.strictEqual(nthPrime(1000), 7919, '<code>nthPrime(1000)</code> should return 7919.'); | 
					
						
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										 |  |  |   - text: <code>nthPrime(10001)</code> should return 104743. | 
					
						
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										 |  |  |     testString: assert.strictEqual(nthPrime(10001), 104743, '<code>nthPrime(10001)</code> should return 104743.'); | 
					
						
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							|  |  |  | ``` | 
					
						
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							|  |  |  | </section> | 
					
						
							|  |  |  | 
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							|  |  |  | ## Challenge Seed
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							|  |  |  | <section id='challengeSeed'> | 
					
						
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							|  |  |  | <div id='js-seed'> | 
					
						
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							|  |  |  | ```js | 
					
						
							|  |  |  | function nthPrime(n) { | 
					
						
							|  |  |  |   // Good luck! | 
					
						
							|  |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | nthPrime(10001); | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | </div> | 
					
						
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							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Solution
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							|  |  |  | <section id='solution'> | 
					
						
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							|  |  |  | ```js | 
					
						
							|  |  |  | const nthPrime = (number)=>{ | 
					
						
							|  |  |  |  let pN = 2; | 
					
						
							|  |  |  |  let step = 0; | 
					
						
							|  |  |  |  while (step<number) { | 
					
						
							|  |  |  |    let isPrime = true; | 
					
						
							|  |  |  |    for(let i = 2;i<pN;i++){ | 
					
						
							|  |  |  |       if(!(pN%i)){ | 
					
						
							|  |  |  |         isPrime = false; | 
					
						
							|  |  |  |         break; | 
					
						
							|  |  |  |       } | 
					
						
							|  |  |  |    } | 
					
						
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										 |  |  |    isPrime ? step++ : ''; | 
					
						
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										 |  |  |     pN++; | 
					
						
							|  |  |  |  } | 
					
						
							|  |  |  |  return pN-1; | 
					
						
							|  |  |  | } | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | </section> |