2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244b1
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2020-12-16 00:37:30 -07:00
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title: 复合赋值之 *=
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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/c83vrfa'
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forumTopicId: 16662
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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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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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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 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`myVar = myVar * 5;`
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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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变量`myVar`等于自身与数值`5`相乘的值。也可以写作这样的形式:
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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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`myVar *= 5;`
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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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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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使用`*=`操作符实现同样的效果。
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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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# --hints--
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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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`a`应该等于`25`。
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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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```js
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assert(a === 25);
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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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`b`应该等于`36`。
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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(b === 36);
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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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`c`应该等于`46`。
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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(c === 46);
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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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应该对每个变量使用`*=`操作符。
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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(code.match(/\*=/g).length === 3);
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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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不要修改注释上面的代码。
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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(
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/var a = 5;/.test(code) &&
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/var b = 12;/.test(code) &&
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/var c = 4\.6;/.test(code)
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);
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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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