Merge two arrays.js

/*
Description:
Write a function that combines two arrays by alternatingly taking elements from each array in turn.

Examples:

[a, b, c, d, e], [1, 2, 3, 4, 5] becomes  [a, 1, b, 2, c, 3, d, 4, e, 5]

[1, 2, 3], [a, b, c, d, e, f] becomes [1, a, 2, b, 3, c, d, e, f]
Points:

The arrays may be of different lengths, with at least one character/digit.
One array will be of string characters (in lower case, a-z), a second of integers (all positive starting at 1).
Inspired by https://adriann.github.io/programming_problems.html
*/
function mergeArrays(a, b) {
  const arr=[];
  let l = Math.max(a.length,b.length)
  for (let i=0; i < l; i++){
  arr.push(a[i])
  arr.push(b[i])
  }
  return arr.filter(v=>v!==undefined)
}