ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
61 lines
1.2 KiB
Markdown
61 lines
1.2 KiB
Markdown
---
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id: bd7123c9c450eddfaeb5bdef
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title: 使用方括号查找字符串中的第N个字符
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cWPVJua'
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forumTopicId: 18343
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dashedName: use-bracket-notation-to-find-the-nth-character-in-a-string
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---
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# --description--
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你也可以使用方括号来获得一个字符串中的其他位置的字符。
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请记住，程序是从`0`开始计数，所以获取第一个字符实际上是\[0]。
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# --instructions--
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让我们使用方括号，把`lastName`变量的第三个字符赋值给`thirdLetterOfLastName`。
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**提示**
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如果你遇到困难了，看看`secondLetterOfFirstName`变量是如何做的。
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# --hints--
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`thirdLetterOfLastName`的值应该是`v`。
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```js
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assert(thirdLetterOfLastName === 'v');
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```
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你应该使用方括号。
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```js
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assert(code.match(/thirdLetterOfLastName\s*?=\s*?lastName\[.*?\]/));
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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(v){return v;})(thirdLetterOfLastName);
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```
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## --seed-contents--
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```js
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// Setup
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var lastName = "Lovelace";
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// Only change code below this line
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var thirdLetterOfLastName = lastName; // Change this line
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```
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# --solutions--
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```js
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var lastName = "Lovelace";
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var thirdLetterOfLastName = lastName[2];
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```
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