45 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			45 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f4a11000cf542c50ffb4
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								title: 'Problem 309: Integer Ladders'
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								challengeType: 5
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								forumTopicId: 301963
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								dashedName: problem-309-integer-ladders
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								---
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								# --description--
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								In the classic "Crossing Ladders" problem, we are given the lengths x and y of two ladders resting on the opposite walls of a narrow, level street. We are also given the height h above the street where the two ladders cross and we are asked to find the width of the street (w).
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								Here, we are only concerned with instances where all four variables are positive integers. For example, if x = 70, y = 119 and h = 30, we can calculate that w = 56.
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								In fact, for integer values x, y, h and 0 < x < y < 200, there are only five triplets (x,y,h) producing integer solutions for w: (70, 119, 30), (74, 182, 21), (87, 105, 35), (100, 116, 35) and (119, 175, 40).
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								For integer values x, y, h and 0 < x < y < 1 000 000, how many triplets (x,y,h) produce integer solutions for w?
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								# --hints--
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								`euler309()` should return 210139.
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								```js
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								assert.strictEqual(euler309(), 210139);
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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 euler309() {
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								  return true;
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								}
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								euler309();
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								```
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								# --solutions--
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								```js
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								// solution required
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								```
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