merge-sort.js

function merge_Arrays(left_sub_array, right_sub_array) {
    let array = []
    while (left_sub_array.length && right_sub_array.length) {
       if (left_sub_array[0] < right_sub_array[0]) {
          array.push(left_sub_array.shift())
       } else {
          array.push(right_sub_array.shift())
       }
    }
    return [ ...array, ...left_sub_array, ...right_sub_array ]
 }
 function merge_sort(unsorted_Array) {
    const middle_index = unsorted_Array.length / 2
    if(unsorted_Array.length < 2) {
       return unsorted_Array
    }
    const left_sub_array = unsorted_Array.splice(0, middle_index)
    return merge_Arrays(merge_sort(left_sub_array),merge_sort(unsorted_Array))
 }
 unsorted_Array = [39, 28, 44, 4, 10, 83, 11];
 console.log("The sorted array will be: ",merge_sort(unsorted_Array));