def mmerge_sort(array)
  t1 = 0
  t11 = 0
  t1 = Time.now.to_f

  def merge_sort(array)
    if array.length <= 1
      return array
    end

    array_size = array.length
    middle = (array.length / 2).round

    left_side = array[0...middle]
    right_side = array[middle...array_size]

    sorted_left = merge_sort(left_side)
    sorted_right = merge_sort(right_side)

    merge(array, sorted_left, sorted_right)

    return array

  end

  def merge(array, sorted_left, sorted_right)
    left_size = sorted_left.length
    right_size = sorted_right.length

    array_pointer = 0
    left_pointer = 0
    right_pointer = 0

    while left_pointer < left_size && right_pointer < right_size
      if sorted_left[left_pointer] < sorted_right[right_pointer]
        array[array_pointer] = sorted_left[left_pointer]
        left_pointer+=1
      else
        array[array_pointer] = sorted_right[right_pointer]
        right_pointer+=1
      end
      array_pointer+=1
    end

    while left_pointer < left_size
        array[array_pointer] = sorted_left[left_pointer]
        left_pointer+=1
        array_pointer+=1
    end

    while right_pointer < right_size
       array[array_pointer] = sorted_right[right_pointer]
       right_pointer+=1
       array_pointer+=1
    end

    return array
  end
  t11 = Time.now.to_f
  t11 =  t11 - t1
  puts t11.to_s + "s"
end