var sortedIndex = function (array, value) {
  var low = 0,
  high = array.length;
  while (low < high) {
    var mid = (low + high) >>> 1;
    if (array[mid] < value) low = mid + 1;
    else high = mid;
  }
  return low;
};

var sortedInsert = function(arr, el) {
  arr.splice(sortedIndex(arr, el), 0, el);
  return arr;
};