Introduction

Inverting an array in JavaScript is a relatively simple task that can be accomplished using a few different methods. In this article, we will discuss the various ways to invert an array in JavaScript, including using the built-in reverse() method, using a for loop, and using the reduce() method. We will also discuss the differences between these methods and when it is best to use each one. By the end of this article, you should have a good understanding of how to invert an array in JavaScript.

Solution

//Using a for loop

function invertArray(arr) {
let newArr = [];
for (let i = arr.length – 1; i >= 0; i–) {
newArr.push(arr[i]);
}
return newArr;
}

//Using the reverse() method

function invertArray(arr) {
return arr.reverse();
}

var abc = ['S', 'L', 'M', 20, 30, 60];

var updated = [];
var mid = abc.length/2;

for (var i=0; i< mid;i++) {
   updated.push(abc[i]);
   updated.push(abc[mid+i]);
}

console.log(updated);

Solved: How to Invert an Array in JavaScript

Inverting an array in JavaScript is a simple task that can be accomplished with a few lines of code. The process involves looping through the array and swapping the elements at each index. This can be done using a for loop or a while loop. In this article, we will discuss how to invert an array in JavaScript using both methods.

Using a For Loop

The most straightforward way to invert an array in JavaScript is to use a for loop. This method involves looping through the array and swapping the elements at each index. The code for this is as follows:

for (let i = 0; i < arr.length; i++) {
  let temp = arr[i];
  arr[i] = arr[arr.length - 1 - i];
  arr[arr.length - 1 - i] = temp;
}

In this code, we are looping through the array and swapping the elements at each index. The variable temp is used to store the value of the element at the current index. Then, the element at the current index is swapped with the element at the last index minus the current index. This process is repeated until the loop reaches the middle of the array.

Using a While Loop

Another way to invert an array in JavaScript is to use a while loop. This method is similar to the for loop method, but it is slightly more efficient. The code for this is as follows:

let i = 0;
let j = arr.length - 1;
while (i < j) {
  let temp = arr[i];
  arr[i] = arr[j];
  arr[j] = temp;
  i++;
  j--;
}

In this code, we are looping through the array and swapping the elements at each index. The variables i and j are used to keep track of the current index. The loop will continue until i is greater than or equal to j. This method is more efficient than the for loop method because it only needs to loop through the array once.

Conclusion

Inverting an array in JavaScript is a simple task that can be accomplished with a few lines of code. The process involves looping through the array and swapping the elements at each index. This can be done using a for loop or a while loop. We hope this article has helped you understand how to invert an array in JavaScript.