ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
92 lines
1.9 KiB
Markdown
92 lines
1.9 KiB
Markdown
---
|
|
id: 587d7db9367417b2b2512ba6
|
|
title: 只指定匹配的下限
|
|
challengeType: 1
|
|
forumTopicId: 301366
|
|
dashedName: specify-only-the-lower-number-of-matches
|
|
---
|
|
|
|
# --description--
|
|
|
|
可以使用带有花括号的`数量说明符`来指定匹配模式的上下限。但有时候只想指定匹配模式的下限而不需要指定上限。
|
|
|
|
为此，在第一个数字后面跟一个逗号即可。
|
|
|
|
例如，要匹配至少出现`3`次字母`a`的字符串`"hah"`，正则表达式应该是`/ha{3,}h/`。
|
|
|
|
```js
|
|
let A4 = "haaaah";
|
|
let A2 = "haah";
|
|
let A100 = "h" + "a".repeat(100) + "h";
|
|
let multipleA = /ha{3,}h/;
|
|
multipleA.test(A4); // Returns true
|
|
multipleA.test(A2); // Returns false
|
|
multipleA.test(A100); // Returns true
|
|
```
|
|
|
|
# --instructions--
|
|
|
|
修改正则表达式`haRegex`，匹配包含四个或更多字母`z`的单词`"Hazzah"`。
|
|
|
|
# --hints--
|
|
|
|
你的正则表达式应该使用花括号。
|
|
|
|
```js
|
|
assert(haRegex.source.match(/{.*?}/).length > 0);
|
|
```
|
|
|
|
你的正则表达式不应该匹配`'Hazzah'`。
|
|
|
|
```js
|
|
assert(!haRegex.test('Hazzah'));
|
|
```
|
|
|
|
你的正则表达式不应该匹配`'Hazzzah'`。
|
|
|
|
```js
|
|
assert(!haRegex.test('Hazzzah'));
|
|
```
|
|
|
|
正则表达式应该匹配 `"Hazzzzah"`
|
|
|
|
```js
|
|
assert('Hazzzzah'.match(haRegex)[0].length === 8);
|
|
```
|
|
|
|
你的正则表达式应该匹配`'Hazzzzah'`。
|
|
|
|
```js
|
|
assert('Hazzzzzah'.match(haRegex)[0].length === 9);
|
|
```
|
|
|
|
正则表达式应该匹配 `"Hazzzzzzah"`
|
|
|
|
```js
|
|
assert('Hazzzzzzah'.match(haRegex)[0].length === 10);
|
|
```
|
|
|
|
正则表达式应该匹配 `"Hazzah"` with 30 `z`'s in it.
|
|
|
|
```js
|
|
assert('Hazzzzzzzzzzzzzzzzzzzzzzzzzzzzzzah'.match(haRegex)[0].length === 34);
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
let haStr = "Hazzzzah";
|
|
let haRegex = /change/; // Change this line
|
|
let result = haRegex.test(haStr);
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
let haStr = "Hazzzzah";
|
|
let haRegex = /Haz{4,}ah/; // Change this line
|
|
let result = haRegex.test(haStr);
|
|
```
|