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							|  |  |  | id: 5900f3761000cf542c50fe88 | 
					
						
							|  |  |  | title: 'Problem 9: Special Pythagorean triplet' | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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										 |  |  | forumTopicId: 302205 | 
					
						
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										 |  |  | dashedName: problem-9-special-pythagorean-triplet | 
					
						
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										 |  |  | # --description--
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										 |  |  | A Pythagorean triplet is a set of three natural numbers, `a` < `b` < `c`, for which, | 
					
						
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										 |  |  | <div style='text-align: center;'><var>a</var><sup>2</sup> + <var>b</var><sup>2</sup> = <var>c</var><sup>2</sup></div> | 
					
						
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										 |  |  | For example, 3<sup>2</sup> + 4<sup>2</sup> = 9 + 16 = 25 = 5<sup>2</sup>. | 
					
						
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										 |  |  | There exists exactly one Pythagorean triplet for which `a` + `b` + `c` = 1000. Find the product `abc` such that `a` + `b` + `c` = `n`. | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `specialPythagoreanTriplet(24)` should return a number. | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert(typeof specialPythagoreanTriplet(24) === 'number'); | 
					
						
							|  |  |  | ``` | 
					
						
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										 |  |  | `specialPythagoreanTriplet(24)` should return 480. | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert.strictEqual(specialPythagoreanTriplet(24), 480); | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | `specialPythagoreanTriplet(120)` should return 49920, 55080 or 60000 | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert([49920, 55080, 60000].includes(specialPythagoreanTriplet(120))); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | `specialPythagoreanTriplet(1000)` should return 31875000. | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert.strictEqual(specialPythagoreanTriplet(1000), 31875000); | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | # --seed--
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										 |  |  | ## --seed-contents--
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							|  |  |  | ```js | 
					
						
							|  |  |  | function specialPythagoreanTriplet(n) { | 
					
						
							|  |  |  |  let sumOfabc = n; | 
					
						
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										 |  |  |  return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | specialPythagoreanTriplet(1000); | 
					
						
							|  |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | const specialPythagoreanTriplet = (n)=>{ | 
					
						
							|  |  |  |  let sumOfabc = n; | 
					
						
							|  |  |  |  let a,b,c; | 
					
						
							|  |  |  |  for(a = 1; a<=sumOfabc/3; a++){ | 
					
						
							|  |  |  |  for(b = a+1; b<=sumOfabc/2; b++){ | 
					
						
							|  |  |  |  c = Math.sqrt(a*a+b*b); | 
					
						
							|  |  |  |  if((a+b+c) == sumOfabc){ | 
					
						
							|  |  |  |  return a*b*c; | 
					
						
							|  |  |  |  } | 
					
						
							|  |  |  |  } | 
					
						
							|  |  |  |  } | 
					
						
							|  |  |  | } | 
					
						
							|  |  |  | ``` |