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>
71 lines
1.4 KiB
Markdown
71 lines
1.4 KiB
Markdown
---
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id: cf1111c1c11feddfaeb9bdef
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title: 使用 JavaScript 生成随机分数
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cyWJJs3'
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forumTopicId: 18185
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dashedName: generate-random-fractions-with-javascript
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---
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# --description--
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随机数非常适合用来创建随机行为。
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`Math.random()`用来生成一个在`0`（包括 0）到`1`（不包括 1）之间的随机小数，因此`Math.random()`可能返回 0 但绝不会返回 1。
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**提示**
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[使用赋值运算符存储值](storing-values-with-the-assignment-operator)这一节讲过，所有函数调用将在`return`执行之前解析，因此我们可以返回`Math.random()`函数的值。
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# --instructions--
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更改`randomFraction`使其返回一个随机数而不是`0`。
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# --hints--
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`randomFraction`应该返回一个随机数。
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```js
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assert(typeof randomFraction() === 'number');
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```
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`randomFraction`应该返回一个小数。
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```js
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assert((randomFraction() + '').match(/\./g));
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```
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需要使用`Math.random`生成随机的小数。
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```js
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assert(code.match(/Math\.random/g).length >= 0);
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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(){return randomFraction();})();
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```
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## --seed-contents--
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```js
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function randomFraction() {
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// Only change code below this line
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return 0;
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// Only change code above this line
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}
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```
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# --solutions--
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```js
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function randomFraction() {
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return Math.random();
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}
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```
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