2018-10-10 18:03:03 -04:00
|
|
|
---
|
|
|
|
id: 56533eb9ac21ba0edf2244d7
|
2021-03-14 21:20:39 -06:00
|
|
|
title: 小于或等于运算符
|
2018-10-10 18:03:03 -04:00
|
|
|
challengeType: 1
|
2020-04-29 18:29:13 +08:00
|
|
|
videoUrl: 'https://scrimba.com/c/cNVR7Am'
|
|
|
|
forumTopicId: 16788
|
2021-01-13 03:31:00 +01:00
|
|
|
dashedName: comparison-with-the-less-than-or-equal-to-operator
|
2018-10-10 18:03:03 -04:00
|
|
|
---
|
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
# --description--
|
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
使用小于等于运算符(`<=`)比较两个数字的大小。 如果在小于等于运算符左边的数字小于或者等于右边的数字,它会返回 `true`。 如果在小于等于运算符左边的数字大于右边的数字,它会返回 `false`。 与相等运算符类似,小于或等于运算符会转换数据类型。
|
2020-12-16 00:37:30 -07:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
**例如**
|
2020-04-29 18:29:13 +08:00
|
|
|
|
|
|
|
```js
|
2022-03-23 19:52:04 +05:30
|
|
|
4 <= 5 // true
|
|
|
|
'7' <= 7 // true
|
|
|
|
5 <= 5 // true
|
|
|
|
3 <= 2 // false
|
|
|
|
'8' <= 4 // false
|
2020-04-29 18:29:13 +08:00
|
|
|
```
|
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
# --instructions--
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2022-03-23 19:52:04 +05:30
|
|
|
将小于或等于运算符添加到指示的行,以便返回语句有意义。
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
# --hints--
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(0)` 应该返回 `Smaller Than or Equal to 12`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
|
|
|
```js
|
2020-12-16 00:37:30 -07:00
|
|
|
assert(testLessOrEqual(0) === 'Smaller Than or Equal to 12');
|
|
|
|
```
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(11)` 应该返回 `Smaller Than or Equal to 12`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(testLessOrEqual(11) === 'Smaller Than or Equal to 12');
|
|
|
|
```
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(12)` 应该返回 `Smaller Than or Equal to 12`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(testLessOrEqual(12) === 'Smaller Than or Equal to 12');
|
2018-10-10 18:03:03 -04:00
|
|
|
```
|
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(23)` 应该返回 `Smaller Than or Equal to 24`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(testLessOrEqual(23) === 'Smaller Than or Equal to 24');
|
|
|
|
```
|
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(24)` 应该返回 `Smaller Than or Equal to 24`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(testLessOrEqual(24) === 'Smaller Than or Equal to 24');
|
|
|
|
```
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(25)` 应该返回 `More Than 24`
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(testLessOrEqual(25) === 'More Than 24');
|
|
|
|
```
|
2018-10-10 18:03:03 -04:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
`testLessOrEqual(55)` 应该返回 `More Than 24`
|
2020-04-29 18:29:13 +08:00
|
|
|
|
2018-10-10 18:03:03 -04:00
|
|
|
```js
|
2020-12-16 00:37:30 -07:00
|
|
|
assert(testLessOrEqual(55) === 'More Than 24');
|
|
|
|
```
|
2020-04-29 18:29:13 +08:00
|
|
|
|
2021-03-14 21:20:39 -06:00
|
|
|
应该使用 `<=` 运算符至少两次
|
2020-04-29 18:29:13 +08:00
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
```js
|
|
|
|
assert(code.match(/val\s*<=\s*('|")*\d+('|")*/g).length > 1);
|
2018-10-10 18:03:03 -04:00
|
|
|
```
|
2020-04-29 18:29:13 +08:00
|
|
|
|
2021-01-13 03:31:00 +01:00
|
|
|
# --seed--
|
|
|
|
|
|
|
|
## --seed-contents--
|
|
|
|
|
|
|
|
```js
|
|
|
|
function testLessOrEqual(val) {
|
|
|
|
if (val) { // Change this line
|
|
|
|
return "Smaller Than or Equal to 12";
|
|
|
|
}
|
|
|
|
|
|
|
|
if (val) { // Change this line
|
|
|
|
return "Smaller Than or Equal to 24";
|
|
|
|
}
|
|
|
|
|
|
|
|
return "More Than 24";
|
|
|
|
}
|
|
|
|
|
|
|
|
testLessOrEqual(10);
|
|
|
|
```
|
|
|
|
|
2020-12-16 00:37:30 -07:00
|
|
|
# --solutions--
|
|
|
|
|
2021-01-13 03:31:00 +01:00
|
|
|
```js
|
|
|
|
function testLessOrEqual(val) {
|
|
|
|
if (val <= 12) { // Change this line
|
|
|
|
return "Smaller Than or Equal to 12";
|
|
|
|
}
|
|
|
|
|
|
|
|
if (val <= 24) { // Change this line
|
|
|
|
return "Smaller Than or Equal to 24";
|
|
|
|
}
|
|
|
|
|
|
|
|
return "More Than 24";
|
|
|
|
}
|
|
|
|
```
|