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Tolerim
a month ago

What is the process for populating an existing array with x repetitions?

The question is regarding updating the contents of an existing array with a specific value for a certain number of times. The array in question is initially defined as let arr = [1, 2, 3];. The desired output is to add the specific value (e.g., 5) to the array for a specified number of times (e.g., 2). The code provided is Array(2).fill(5), and the task is to modify this code to produce the desired result of [1, 2, 3, 5, 5].
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Vogi
a month ago
Verified Answer
You can use the concat() method to concatenate two arrays and create a new array that contains all the elements of both arrays. In this case, you can use it to concatenate the original array with an array that contains the specific value repeated for a certain number of times. Here's how you can do it:
let arr = [1, 2, 3];
let specificValue = 5;
let numberOfTimes = 2;

let newArr = arr.concat(Array(numberOfTimes).fill(specificValue));
console.log(newArr); // [1, 2, 3, 5, 5]
In this code snippet, we first define the original array arr, the specific value we want to add specificValue, and the number of times we want to add it numberOfTimes. We then use the concat() method to concatenate arr with an array that contains specificValue repeated for numberOfTimes times using the fill() method. I hope this helps! Let me know if you have any other questions.

Sources

How To Add New Elements To A JavaScript Array - W3docsjavascript - How to count certain elements in array? - Stack OverflowCreate an Array with N elements, same Value in JavaScriptHow to add same elements to javascript array n timesWith JavaScript how would I increment numbers in an array using a for ...
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Tolerim
a month ago
Yes, you can use the concat method to concatenate the original array with a new array created using Array constructor and fill method. Here's an example:
let arr = [1, 2, 3];

arr = arr.concat(Array(2).fill(5));

console.log(arr); // [1, 2, 3, 5, 5]
In this example, we first create a new array with two elements filled with 5 using the Array constructor and fill method. Then, we use the concat method to concatenate this new array with the original array arr. Finally, we assign the concatenated array back to arr and log it to the console to get the desired output.
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