2018-10-10 22:03:03 +00:00
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---
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id: 56533eb9ac21ba0edf2244b1
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2021-03-04 17:49:46 +00:00
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title: 复合赋值之 *=
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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/c83vrfa'
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forumTopicId: 16662
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2021-01-13 02:31:00 +00:00
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dashedName: compound-assignment-with-augmented-multiplication
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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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2021-03-04 17:49:46 +00:00
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`*=` 操作符是让变量与一个数相乘并赋值。
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2018-10-10 22:03:03 +00:00
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2021-04-05 15:04:04 +00:00
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```js
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myVar = myVar * 5;
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```
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2018-10-10 22:03:03 +00:00
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2021-04-05 15:04:04 +00:00
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将 `myVar` 乘以 `5`。 等价于:
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2018-10-10 22:03:03 +00:00
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2021-04-05 15:04:04 +00:00
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```js
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myVar *= 5;
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```
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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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# --instructions--
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2018-10-10 22:03:03 +00:00
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2021-04-05 15:04:04 +00:00
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使用 `*=` 操作符对 `a`、`b` 和 `c` 实现赋值相乘操作。
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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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2018-10-10 22:03:03 +00:00
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2021-03-04 17:49:46 +00:00
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`a` 应该等于`25`。
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2020-04-29 10:29:13 +00:00
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2020-12-16 07:37:30 +00:00
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```js
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assert(a === 25);
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2018-10-10 22:03:03 +00:00
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```
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2021-03-04 17:49:46 +00:00
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`b` 应该等于`36`。
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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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```js
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assert(b === 36);
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```
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2018-10-10 22:03:03 +00:00
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2021-03-04 17:49:46 +00:00
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`c` 应该等于`46`。
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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(c === 46);
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2018-10-10 22:03:03 +00:00
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```
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2021-03-04 17:49:46 +00:00
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应该对每个变量使用 `*=` 操作符。
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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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```js
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assert(code.match(/\*=/g).length === 3);
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```
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2018-10-10 22:03:03 +00:00
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2021-03-04 17:49:46 +00:00
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不要修改注释上面的代码。
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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(
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2021-10-27 15:10:57 +00:00
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/let a = 5;/.test(code) &&
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/let b = 12;/.test(code) &&
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/let c = 4\.6;/.test(code)
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2020-12-16 07:37:30 +00:00
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);
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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(a,b,c){ return "a = " + a + ", b = " + b + ", c = " + c; })(a,b,c);
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```
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## --seed-contents--
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```js
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2021-10-27 15:10:57 +00:00
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let a = 5;
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let b = 12;
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let c = 4.6;
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2021-01-13 02:31:00 +00:00
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// Only change code below this line
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a = a * 5;
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b = 3 * b;
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c = c * 10;
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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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2021-10-27 15:10:57 +00:00
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let a = 5;
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let b = 12;
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let c = 4.6;
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2021-01-13 02:31:00 +00:00
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a *= 5;
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b *= 3;
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c *= 10;
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```
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