47 lines
		
	
	
		
			866 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			47 lines
		
	
	
		
			866 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f4461000cf542c50ff58
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								title: 'Problem 217: Balanced Numbers'
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								challengeType: 5
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								forumTopicId: 301859
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								dashedName: problem-217-balanced-numbers
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								---
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								# --description--
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								A positive integer with k (decimal) digits is called balanced if its first ⌈k/2⌉ digits sum to the same value as its last ⌈k/2⌉ digits, where ⌈x⌉, pronounced ceiling of x, is the smallest integer ≥ x, thus ⌈π⌉ = 4 and ⌈5⌉ = 5.
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								So, for example, all palindromes are balanced, as is 13722.
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								Let T(n) be the sum of all balanced numbers less than 10n.
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								Thus: T(1) = 45, T(2) = 540 and T(5) = 334795890.
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								Find T(47) mod 315
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								# --hints--
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								`euler217()` should return 6273134.
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								```js
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								assert.strictEqual(euler217(), 6273134);
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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 euler217() {
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								  return true;
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								}
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								euler217();
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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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