2018-10-10 22:03:03 +00:00
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---
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id: 5900f5471000cf542c510059
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2020-12-16 07:37:30 +00:00
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title: 问题474:除数的最后数字
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2018-10-10 22:03:03 +00:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 02:31:00 +00:00
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dashedName: problem-474-last-digits-of-divisors
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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对于正整数n和数字d,我们将F(n,d)定义为n的除数的数,其最后的数字等于d。例如,F(84,4)= 3.在84的除数中(1,2,3,4,6,7,12,14,21,28,42,84),其中三个(4,14) ,84)有最后一位数字4。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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我们还可以验证F(12!,12)= 11和F(50!,123)= 17888。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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找到F(106!,65432)modulo(1016 + 61)。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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`euler474()`应该返回9690646731515010。
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert.strictEqual(euler474(), 9690646731515010);
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2018-10-10 22:03:03 +00:00
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```
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2021-01-13 02:31:00 +00:00
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# --seed--
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## --seed-contents--
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```js
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function euler474() {
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return true;
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}
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euler474();
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```
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2020-12-16 07:37:30 +00:00
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# --solutions--
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2020-08-13 15:24:35 +00:00
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2021-01-13 02:31:00 +00:00
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```js
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// solution required
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```
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