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>
45 lines
978 B
Markdown
45 lines
978 B
Markdown
---
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id: 5900f5001000cf542c510012
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title: 问题404：交叉椭圆
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challengeType: 5
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videoUrl: ''
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dashedName: problem-404-crisscross-ellipses
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---
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# --description--
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Ea是椭圆，其形式为x2 + 4y2 = 4a2。 Ea'是Ea的旋转图像，绕原点O（0,0）逆时针旋转θ度0°<θ<90°。
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b是距离原点最近的两个交点的原点的距离，c是另外两个交点的距离。如果a，b和c是正整数，我们称有序三元组（a，b，c）为规范椭圆体三元组。例如，（209,247,286）是规范的椭圆体三重态。
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令C（N）为a≤N的不同规范椭球三胞胎（a，b，c）的数量。可以证实C（103）= 7，C（104）= 106和C（106）= 11845 。
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找到C（1017）。
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# --hints--
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`euler404()`应该返回1199215615081353。
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```js
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assert.strictEqual(euler404(), 1199215615081353);
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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 euler404() {
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return true;
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}
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euler404();
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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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