2018-10-10 22:03:03 +00:00
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---
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id: cf1111c1c11feddfaeb3bdef
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2021-03-15 03:20:39 +00:00
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title: 加法运算
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2018-10-10 22:03:03 +00:00
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challengeType: 1
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2020-04-29 10:29:13 +00:00
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videoUrl: 'https://scrimba.com/c/cM2KBAG'
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forumTopicId: 16650
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2021-01-13 02:31:00 +00:00
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dashedName: add-two-numbers-with-javascript
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2018-10-10 22:03:03 +00:00
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2021-03-15 03:20:39 +00:00
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`Number` 是 JavaScript 中的一种数据类型,用来表示数值。
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2018-10-10 22:03:03 +00:00
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2021-03-15 03:20:39 +00:00
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现在我们来尝试在 JavaScript 中做加法运算。
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2018-10-10 22:03:03 +00:00
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2021-03-15 03:20:39 +00:00
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JavaScript 中,我们通过符号 `+` 来进行加法运算。
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2018-10-10 22:03:03 +00:00
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2021-03-15 03:20:39 +00:00
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**代码示例:**
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2018-10-10 22:03:03 +00:00
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```js
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2021-10-27 15:10:57 +00:00
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const myVar = 5 + 10;
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2018-10-10 22:03:03 +00:00
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```
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2021-03-15 03:20:39 +00:00
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现在,变量 `myVar` 的值为 `15`。
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2020-12-16 07:37:30 +00:00
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# --instructions--
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2018-10-10 22:03:03 +00:00
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2021-03-15 03:20:39 +00:00
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请改变数字 `0` 让变量 sum 的值为 `20`。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2021-03-15 03:20:39 +00:00
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`sum` 的值应该等于 `20`。
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2018-10-10 22:03:03 +00:00
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```js
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assert(sum === 20);
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2018-10-10 22:03:03 +00:00
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```
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2021-03-15 03:20:39 +00:00
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请使用 `+` 运算符。
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2020-04-29 10:29:13 +00:00
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert(/\+/.test(code));
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2018-10-10 22:03:03 +00:00
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```
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2020-04-29 10:29:13 +00:00
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2021-01-13 02:31:00 +00:00
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# --seed--
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## --after-user-code--
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```js
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(function(z){return 'sum = '+z;})(sum);
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```
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## --seed-contents--
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```js
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const sum = 10 + 0;
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```
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2020-12-16 07:37:30 +00:00
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# --solutions--
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2021-01-13 02:31:00 +00:00
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```js
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const sum = 10 + 10;
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2021-01-13 02:31:00 +00:00
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```
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