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>
53 lines
1.1 KiB
Markdown
53 lines
1.1 KiB
Markdown
---
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id: 5900f3b31000cf542c50fec6
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title: 关卡 71：有序分数
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challengeType: 5
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forumTopicId: 302184
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dashedName: problem-71-ordered-fractions
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---
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# --description--
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考虑形如 `n`/`d` 的分数，其中 `n` 和 `d` 均为正整数。如果 `n`<`d`，且最大公约数 HCF(`n`,`d`)=1，则该分数被称为最简真分数。
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如果我们将 `d` ≤ 8 的最简真分数构成的集合按大小升序列出，将得到：
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<div style='text-align: center;'>1/8, 1/7, 1/6, 1/5, 1/4, 2/7, 1/3, 3/8, <strong>2/5</strong>, 3/7, 1/2, 4/7, 3/5, 5/8, 2/3, 5/7, 3/4, 4/5, 5/6, 6/7, 7/8</div>
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可以看出 2/5 是 3/7 的直接左邻的分数。
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将所有 `d` ≤ 1,000,000 的最简真分数按大小升序排列，求此时 3/7 直接左邻的分数的分子。
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# --hints--
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`orderedFractions()` 应该返回一个数字。
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```js
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assert(typeof orderedFractions() === 'number');
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```
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`orderedFractions()` 应该返回 428570。
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```js
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assert.strictEqual(orderedFractions(), 428570);
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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 orderedFractions() {
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return true;
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}
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orderedFractions();
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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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