77 lines
1.7 KiB
Markdown
77 lines
1.7 KiB
Markdown
---
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id: 587d7dab367417b2b2512b6e
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title: Use the every Method to Check that Every Element in an Array Meets a Criteria
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challengeType: 1
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forumTopicId: 301312
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dashedName: use-the-every-method-to-check-that-every-element-in-an-array-meets-a-criteria
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---
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# --description--
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The `every` method works with arrays to check if *every* element passes a particular test. It returns a Boolean value - `true` if all values meet the criteria, `false` if not.
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For example, the following code would check if every element in the `numbers` array is less than 10:
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```js
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var numbers = [1, 5, 8, 0, 10, 11];
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numbers.every(function(currentValue) {
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return currentValue < 10;
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});
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// Returns false
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```
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# --instructions--
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Use the `every` method inside the `checkPositive` function to check if every element in `arr` is positive. The function should return a Boolean value.
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# --hints--
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Your code should use the `every` method.
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```js
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assert(code.match(/\.every/g));
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```
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`checkPositive([1, 2, 3, -4, 5])` should return `false`.
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```js
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assert.isFalse(checkPositive([1, 2, 3, -4, 5]));
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```
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`checkPositive([1, 2, 3, 4, 5])` should return `true`.
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```js
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assert.isTrue(checkPositive([1, 2, 3, 4, 5]));
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```
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`checkPositive([1, -2, 3, -4, 5])` should return `false`.
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```js
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assert.isFalse(checkPositive([1, -2, 3, -4, 5]));
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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 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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# --solutions--
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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.every(num => num > 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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