42 lines
1.2 KiB
Markdown
42 lines
1.2 KiB
Markdown
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---
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title: Finders Keepers
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---
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## Problem Explanation
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We need to return the element from an array that passes a function. Both the `function` and the `array` are passed into our function `findElement(arr, func)`.
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## Hint: 1
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Looking through the array can be done with a `for` loop.
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>*try to solve the problem now*
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## Hint: 2
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`num` is passed to the function. We will need to set it to the elements we want to check with the function.
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>*try to solve the problem now*
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## Hint: 3
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Do not forget, if none of the numbers in the array pass the test, it should return `undefined`.
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>*try to solve the problem now*
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## Basic Solution
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```javascript
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function findElement(arr, func) {
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let num = 0;
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for(var i = 0; i < arr.length; i++) {
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num = arr[i];
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if (func(num)) {
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return num;
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}
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}
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return undefined;
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}
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```
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## Code Explanation
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* Challenge asks us to look through array. This is done using a `for` loop.
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* The `num` variable is being passed into the function, so we set it to each index in our array.
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* The pre-defined function already checks each number for us, so if it is "true", we return that num.
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* If none of the numbers in the array pass the function's test, we return undefined.
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