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>
80 lines
1.8 KiB
Markdown
80 lines
1.8 KiB
Markdown
---
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id: 5cc0bd7a49b71cb96132e54c
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title: 使用递归来创建一个数字序列
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challengeType: 1
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forumTopicId: 301180
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dashedName: use-recursion-to-create-a-range-of-numbers
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---
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# --description--
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接着上一个挑战，有另外一个机会来创建递归函数解决问题。
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# --instructions--
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定义好了 `rangeOfNumbers` 函数，包含两个参数。函数应该返回一个连续数字数组，`startNum` 参数开始 `endNum` 参数截止。开始的数字小于或等于截止数字。函数必需递归调用自身，不能使用任意形式的循环。要考虑到 `startNum` 和 `endNum` 相同的情况。
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# --hints--
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函数应该返回一个数组。
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```js
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assert(Array.isArray(rangeOfNumbers(5, 10)));
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```
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不能包含循环语句（`for` 或者 `while` 或者高阶函数比如 `forEach`、`map`、`filter` 或者 `reduce`）。
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```js
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assert(!removeJSComments(code).match(/for|while|forEach|map|filter|reduce/g));
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```
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`rangeOfNumbers` 应该使用递归函数（调用自身）来完成这个挑战。
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```js
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assert(
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removeJSComments(rangeOfNumbers.toString()).match(/rangeOfNumbers\s*\(.+\)/)
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);
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```
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`rangeOfNumbers(1, 5)` 应该返回 `[1, 2, 3, 4, 5]`。
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```js
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assert.deepStrictEqual(rangeOfNumbers(1, 5), [1, 2, 3, 4, 5]);
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```
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`rangeOfNumbers(6, 9)` 应该返回 `[6, 7, 8, 9]`。
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```js
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assert.deepStrictEqual(rangeOfNumbers(6, 9), [6, 7, 8, 9]);
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```
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`rangeOfNumbers(4, 4)` 应该返回 `[4]`。
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```js
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assert.deepStrictEqual(rangeOfNumbers(4, 4), [4]);
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```
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# --seed--
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## --seed-contents--
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```js
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function rangeOfNumbers(startNum, endNum) {
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return [];
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};
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```
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# --solutions--
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```js
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function rangeOfNumbers(startNum, endNum) {
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if (endNum - startNum === 0) {
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return [startNum];
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} else {
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var numbers = rangeOfNumbers(startNum, endNum - 1);
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numbers.push(endNum);
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return numbers;
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}
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}
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```
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