72 lines
1.1 KiB
Markdown
72 lines
1.1 KiB
Markdown
---
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id: 5900f5241000cf542c510037
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challengeType: 5
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videoUrl: ''
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localeTitle: 问题440:GCD和平铺
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---
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## Description
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<section id="description">
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我们要完全平铺一块长度为n且高度为1的板,上面有1×2块或1×1块,上面有一个十进制数字:
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例如,以下是铺砌长度为n = 8的板的一些方法:
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令T(n)是如上所述的平铺长度为n的板的方式的数量。
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例如,T(1)= 10且T(2)= 101。
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令S(L)为1≤a,b,c≤L的三次和∑a,b,c gcd(T(ca),T(cb))。
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例如:
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S(2)= 10444
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S(3)= 1292115238446807016106539989
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S(4)模数987898789 = 670616280。
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找出S(2000)mod 987898898。
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</section>
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>euler440()</code>应该返回970746056。
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testString: assert.strictEqual(euler440(), 970746056);
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function euler440() {
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// Good luck!
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return true;
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}
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euler440();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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/section>
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