Javascript Array mergeSort(arr)

// merge sort//from w  w  w  . j  av  a2 s. c  o m
var mergeSort = function(arr) {
  var left = arr.slice(0, Math.floor(arr.length / 2));
  var right = arr.slice(Math.floor(arr.length / 2));

  if (arr.length < 2) {
    return arr;
  }

  return mergeArrays(mergeSort(left), mergeSort(right));
}