Alternatively merge two different arrays

An algorithm to merge two different arrays alternatively in to third array in javascript.

Example

Input:
[1, 2, 3, 4, 5, 6, 7 , 8]
[11, 22, 33, 44]

Output:
[1, 11, 2, 22, 3, 33, 4, 44, 5, 6, 7, 8]

A simple brute force approach to alternatively merge two arrays.

Implementation

• We will copy each element from the both the arrays alternatively in the the third array till there is element in any one of them.
• Then we will check if there is still element in any of the arrays then add them to the third array.

let alternateMerge = (arr1, arr2, n1 = arr1.length, n2 = arr2.length) => {
  let i = 0, j = 0;
  let temp = [];
  
  //Add each element from both the array
  while(i < n1 && j < n2){
    temp.push(arr1[i], arr2[j]);
    i++;
    j++;
  }
  
  //If there is still element in first array
  //then add them
  while(i < n1){
    temp.push(arr1[i]);
    i++;
  }
  
  //If there is still element in second array
  //then add them
  while(j < n2){
    temp.push(arr2[j]);
    j++;
  }
  
  return temp;
}

Input:
console.log(alternateMerge([1, 2, 3, 4, 5, 6, 7 , 8],[11, 22, 33, 44]));

Output:
[1, 11, 2, 22, 3, 33, 4, 44, 5, 6, 7, 8]

Time complexity: O(n1 + n2).
Space complexity: O(n1 + n2).