ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
47 lines
866 B
Markdown
47 lines
866 B
Markdown
---
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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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