2018-10-10 18:03:03 -04:00
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---
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id: 5690307fddb111c6084545d7
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2020-12-16 00:37:30 -07:00
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title: if else 语句中的逻辑顺序
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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/cwNvMUV'
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forumTopicId: 18228
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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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`if`、`else if`语句中代码的执行顺序是很重要的。
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2020-04-29 18:29:13 +08:00
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在条件判断语句中,代码的执行顺序是从上到下,所以你需要考虑清楚先执行哪一句,后执行哪一句。
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2020-12-16 00:37:30 -07:00
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2020-04-29 18:29:13 +08:00
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这有两个例子。
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2020-12-16 00:37:30 -07:00
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2020-04-29 18:29:13 +08:00
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第一个例子:
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```js
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function foo(x) {
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if (x < 1) {
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return "Less than one";
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} else if (x < 2) {
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return "Less than two";
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} else {
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return "Greater than or equal to two";
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}
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}
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```
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第二个例子更改了代码的执行顺序:
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```js
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function bar(x) {
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if (x < 2) {
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return "Less than two";
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} else if (x < 1) {
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return "Less than one";
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} else {
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return "Greater than or equal to two";
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}
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}
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```
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这两个函数看起来几乎一模一样,我们传一个值进去看看它们有什么区别。
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```js
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foo(0) // "Less than one"
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bar(0) // "Less than two"
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```
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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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2020-04-29 18:29:13 +08:00
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更改函数的逻辑顺序以便通过所有的测试用例。
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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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`orderMyLogic(4)`应该返回 "Less than 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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```js
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assert(orderMyLogic(4) === 'Less than 5');
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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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`orderMyLogic(6)`应该返回 "Less than 10"。
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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(orderMyLogic(6) === 'Less than 10');
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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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`orderMyLogic(11)`应该返回 "Greater than or equal to 10"。
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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(orderMyLogic(11) === 'Greater than or equal to 10');
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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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