2021-05-05 10:13:49 -07:00
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---
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id: 56533eb9ac21ba0edf2244ae
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title: 求餘運算
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cWP24Ub'
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forumTopicId: 18184
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dashedName: finding-a-remainder-in-javascript
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---
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# --description--
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<dfn>remainder</dfn> 求餘運算符 `%` 返回兩個數相除得到的餘數
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**示例**
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<blockquote>5 % 2 = 1 因爲<br>Math.floor(5 / 2) = 2 (商)<br>2 * 2 = 4<br>5 - 4 = 1 (餘數)</blockquote>
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**用法**
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在數學中,判斷一個數是奇數還是偶數,只需要判斷這個數除以 `2` 得到的餘數是 0 還是 1。
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<blockquote>17 % 2 = 1(17 是奇數)<br>48 % 2 = 0(48 是偶數)</blockquote>
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**提示**餘數運算符(<dfn>remainder</dfn>)有時被錯誤地稱爲“模數”運算符。 它與模數非常相似,但不能用於負數的運算。
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# --instructions--
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使用 <dfn>remainder</dfn> (`%`)運算符,計算 `11` 除以 `3` 的餘數,並把餘數賦給變量 `remainder`。
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# --hints--
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變量 `remainder` 應該被初始化。
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```js
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2021-10-27 15:10:57 +00:00
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assert(/(const|let|var)\s+?remainder/.test(code));
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```
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`remainder` 的值應該等於 `2`。
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```js
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assert(remainder === 2);
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```
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你應該使用 `%` 運算符。
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```js
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assert(/\s+?remainder\s*?=\s*?.*%.*;?/.test(code));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(y){return 'remainder = '+y;})(remainder);
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```
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## --seed-contents--
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```js
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const remainder = 0;
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```
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# --solutions--
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```js
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const remainder = 11 % 3;
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```
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