2018-10-10 22:03:03 +00:00
|
|
|
|
---
|
|
|
|
|
id: 5900f3861000cf542c50fe99
|
2020-12-16 07:37:30 +00:00
|
|
|
|
title: 问题26:互惠周期
|
2018-10-10 22:03:03 +00:00
|
|
|
|
challengeType: 5
|
|
|
|
|
videoUrl: ''
|
|
|
|
|
---
|
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
# --description--
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
单位分数在分子中包含1。给出分母2到10的单位分数的十进制表示:
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
<sup><sub>二分之一</sub></sup>
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
= 0.5
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
<sup><sub>三分之一</sub></sup>
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
= 0(3)
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
<sup><sub>四分之一</sub></sup>
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
= 0.25
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
<sup>的<sub>1/5</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0.2
|
|
|
|
|
|
|
|
|
|
<sup><sub>六分之一</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0.1(6)
|
|
|
|
|
|
|
|
|
|
<sup><sub>七分之一</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0(142857)
|
|
|
|
|
|
|
|
|
|
<sup><sub>八分之一</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0.125
|
|
|
|
|
|
|
|
|
|
<sup><sub>九分之一</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0(1)
|
|
|
|
|
|
|
|
|
|
<sup><sub>一十分之一</sub></sup>
|
|
|
|
|
|
|
|
|
|
= 0.1
|
|
|
|
|
|
|
|
|
|
其中0.1(6)表示0.166666 ...,并具有1位循环周期。可以看出,
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
<sup>1</sup>
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
/
|
|
|
|
|
|
|
|
|
|
<sub>7</sub>
|
|
|
|
|
|
|
|
|
|
具有6位循环周期。找到`d` < `n`的值,其中
|
|
|
|
|
|
|
|
|
|
<sup>1</sup>
|
|
|
|
|
|
|
|
|
|
/
|
|
|
|
|
|
|
|
|
|
<sub>d</sub>
|
|
|
|
|
|
|
|
|
|
包含其小数部分中最长的循环周期。
|
|
|
|
|
|
|
|
|
|
# --hints--
|
|
|
|
|
|
|
|
|
|
`reciprocalCycles(700)`应该返回659。
|
|
|
|
|
|
|
|
|
|
```js
|
|
|
|
|
assert(reciprocalCycles(700) == 659);
|
2018-10-10 22:03:03 +00:00
|
|
|
|
```
|
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
`reciprocalCycles(800)`应该返回743。
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
```js
|
|
|
|
|
assert(reciprocalCycles(800) == 743);
|
|
|
|
|
```
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
`reciprocalCycles(900)`应该返回887。
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
```js
|
|
|
|
|
assert(reciprocalCycles(900) == 887);
|
|
|
|
|
```
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
`reciprocalCycles(1000)`应该返回983。
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
|
|
|
|
```js
|
2020-12-16 07:37:30 +00:00
|
|
|
|
assert(reciprocalCycles(1000) == 983);
|
2018-10-10 22:03:03 +00:00
|
|
|
|
```
|
2020-08-13 15:24:35 +00:00
|
|
|
|
|
2020-12-16 07:37:30 +00:00
|
|
|
|
# --solutions--
|
|
|
|
|
|