96 lines
1.2 KiB
Markdown
96 lines
1.2 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244b1
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title: 複合賦值之 *=
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c83vrfa'
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forumTopicId: 16662
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dashedName: compound-assignment-with-augmented-multiplication
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---
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# --description--
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`*=` 操作符是讓變量與一個數相乘並賦值。
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```js
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myVar = myVar * 5;
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```
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將 `myVar` 乘以 `5`。 等價於：
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```js
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myVar *= 5;
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```
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# --instructions--
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使用 `*=` 操作符對 `a`、`b` 和 `c` 實現賦值相乘操作。
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# --hints--
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`a` 應該等於`25`。
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```js
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assert(a === 25);
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```
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`b` 應該等於`36`。
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```js
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assert(b === 36);
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```
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`c` 應該等於`46`。
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```js
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assert(c === 46);
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```
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應該對每個變量使用 `*=` 操作符。
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```js
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assert(code.match(/\*=/g).length === 3);
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```
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不要修改註釋上面的代碼。
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```js
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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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```
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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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var a = 5;
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var b = 12;
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var c = 4.6;
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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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# --solutions--
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```js
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var a = 5;
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var b = 12;
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var c = 4.6;
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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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