2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244df
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2020-12-16 00:37:30 -07:00
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title: 在 Switch 语句添加多个相同选项
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2018-10-10 18:03:03 -04:00
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challengeType: 1
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2020-04-29 18:29:13 +08:00
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videoUrl: 'https://scrimba.com/c/cdBKWCV'
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forumTopicId: 18242
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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如果你忘了给`switch`的每一条`case`添加`break`,那么直到遇见`break`为止,后续的`case`会一直执行。如果你想为多个不同的输入设置相同的结果,可以这样写:
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2020-04-29 18:29:13 +08:00
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```js
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switch(val) {
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case 1:
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case 2:
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case 3:
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result = "1, 2, or 3";
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break;
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case 4:
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result = "4 alone";
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}
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```
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这样,1、2、3 都会有相同的结果。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --instructions--
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请写一个`switch`语句,根据输入的`val`的范围得出对应的`answer`:
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`1-3` - "Low"
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`4-6` - "Mid"
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`7-9` - "High"
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**提示:**
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你的`case`应基于范围中的每一个数字编写。
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# --hints--
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`sequentialSizes(1)`应该返回 "Low"。
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```js
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assert(sequentialSizes(1) === 'Low');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(2)`应该返回 "Low"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(sequentialSizes(2) === 'Low');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(3)`应该返回 "Low"。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(sequentialSizes(3) === 'Low');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(4)`应该返回 "Mid"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(sequentialSizes(4) === 'Mid');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(5)`应该返回 "Mid"。
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```js
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assert(sequentialSizes(5) === 'Mid');
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```
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`sequentialSizes(6)`应该返回 "Mid"。
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```js
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assert(sequentialSizes(6) === 'Mid');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(7)`应该返回 "High"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(sequentialSizes(7) === 'High');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(8)`应该返回 "High"。
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```js
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assert(sequentialSizes(8) === 'High');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`sequentialSizes(9)`应该返回 "High"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(sequentialSizes(9) === 'High');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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你不应使用`if`或`else`语句。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(!/else/g.test(code) || !/if/g.test(code));
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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你应该编写 9 个`case`语句。
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2020-04-29 18:29:13 +08:00
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(code.match(/case/g).length === 9);
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2018-10-10 18:03:03 -04:00
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```
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2020-04-29 18:29:13 +08:00
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2020-12-16 00:37:30 -07:00
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# --solutions--
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