80 lines
2.0 KiB
Markdown
80 lines
2.0 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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---
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## Description
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<section id='description'>
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The <code>every</code> method works with arrays to check if <em>every</em> element passes a particular test. It returns a Boolean value - <code>true</code> if all values meet the criteria, <code>false</code> if not.
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For example, the following code would check if every element in the <code>numbers</code> 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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</section>
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## Instructions
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<section id='instructions'>
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Use the <code>every</code> method inside the <code>checkPositive</code> function to check if every element in <code>arr</code> is positive. The function should return a Boolean value.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: Your code should use the <code>every</code> method.
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testString: assert(code.match(/\.every/g));
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- text: <code>checkPositive([1, 2, 3, -4, 5])</code> should return <code>false</code>.
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testString: assert.isFalse(checkPositive([1, 2, 3, -4, 5]));
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- text: <code>checkPositive([1, 2, 3, 4, 5])</code> should return <code>true</code>.
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testString: assert.isTrue(checkPositive([1, 2, 3, 4, 5]));
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- text: <code>checkPositive([1, -2, 3, -4, 5])</code> should return <code>false</code>.
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testString: assert.isFalse(checkPositive([1, -2, 3, -4, 5]));
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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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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</div>
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</section>
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## Solution
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<section id='solution'>
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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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</section>
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