2018-10-10 18:03:03 -04:00
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---
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id: 587d7dab367417b2b2512b6f
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2020-12-16 00:37:30 -07:00
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title: 使用 some 方法检查数组中是否有元素是否符合条件
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2018-10-10 18:03:03 -04:00
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challengeType: 1
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2020-08-05 16:38:04 +08:00
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forumTopicId: 301314
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2021-01-13 03:31:00 +01:00
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dashedName: use-the-some-method-to-check-that-any-elements-in-an-array-meet-a-criteria
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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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`some`方法用于检测数组中*任何*元素是否满足指定条件。如果有一个元素满足条件,返回布尔值`true`,反之返回`false`。
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举个例子,下面的代码检测数组`numbers`中是否有元素小于10:
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2020-08-05 16:38:04 +08:00
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```js
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var numbers = [10, 50, 8, 220, 110, 11];
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numbers.some(function(currentValue) {
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return currentValue < 10;
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});
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// Returns true
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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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2020-12-16 00:37:30 -07:00
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在`checkPositive`函数值中使用`some`检查`arr`中是否有元素为正数,函数应返回一个布尔值。
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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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应该使用`some`method.
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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(code.match(/\.some/g));
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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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`checkPositive([1, 2, 3, -4, 5])`应返回`true`。
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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(checkPositive([1, 2, 3, -4, 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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`checkPositive([1, 2, 3, 4, 5])`应返回`true`。
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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(checkPositive([1, 2, 3, 4, 5]));
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```
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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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`checkPositive([-1, -2, -3, -4, -5])`应返回`false`。
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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(!checkPositive([-1, -2, -3, -4, -5]));
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2018-10-10 18:03:03 -04:00
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```
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2020-08-05 16:38:04 +08:00
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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function checkPositive(arr) {
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// Only change code below this line
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// Only change code above this line
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}
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checkPositive([1, 2, 3, -4, 5]);
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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```js
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function checkPositive(arr) {
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// Only change code below this line
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return arr.some(elem => elem > 0);
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// Only change code above this line
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}
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checkPositive([1, 2, 3, -4, 5]);
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```
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