56 lines
1.3 KiB
Markdown
56 lines
1.3 KiB
Markdown
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---
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id: 5900f46b1000cf542c50ff7d
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challengeType: 5
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title: 'Problem 254: Sums of Digit Factorials'
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videoUrl: ''
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localeTitle: 问题254:数字因子的总和
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---
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## Description
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<section id="description">将f(n)定义为n的数字的阶乘的总和。例如,f(342)= 3! + 4! + 2! = 32。 <p>将sf(n)定义为f(n)的数字之和。所以sf(342)= 3 + 2 = 5。 </p><p>将g(i)定义为最小的正整数n,使得sf(n)= i。虽然sf(342)是5,但sf(25)也是5,并且可以证实g(5)是25。 </p><p>将sg(i)定义为g(i)的数字之和。所以sg(5)= 2 + 5 = 7。 </p><p>此外,可以证实g(20)是267并且1≤i≤20的Σsg(i)是156。 </p><p>什么是Σsg(i)1≤i≤150? </p></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>euler254()</code>应该返回8184523820510。
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testString: 'assert.strictEqual(euler254(), 8184523820510, "<code>euler254()</code> should return 8184523820510.");'
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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 euler254() {
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// Good luck!
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return true;
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}
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euler254();
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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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