64 lines
1.0 KiB
Markdown
64 lines
1.0 KiB
Markdown
---
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id: 5900f5471000cf542c510059
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challengeType: 5
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title: 'Problem 474: Last digits of divisors'
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---
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## Description
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<section id='description'>
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For a positive integer n and digits d, we define F(n, d) as the number of the divisors of n whose last digits equal d.
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For example, F(84, 4) = 3. Among the divisors of 84 (1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84), three of them (4, 14, 84) have the last digit 4.
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We can also verify that F(12!, 12) = 11 and F(50!, 123) = 17888.
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Find F(106!, 65432) modulo (1016 + 61).
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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>euler474()</code> should return 9690646731515010.
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testString: assert.strictEqual(euler474(), 9690646731515010);
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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 euler474() {
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// Good luck!
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return true;
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}
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euler474();
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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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