old_contents: """
  radix sort
  complexity: O(nk + n) . n is the size of input list and k is the digit length of the number
  """
  def radix_sort(arr, simulation=False):
      position = 1
      max_number = max(arr)
  
      iteration = 0
      if simulation:
          print("iteration", iteration, ":", *arr)
  
      while position < max_number:
          queue_list = [list() for _ in range(10)]
  
          for num in arr:
              digit_number = num // position % 10
              queue_list[digit_number].append(num)
  
          index = 0
          for numbers in queue_list:
              for num in numbers:
                  arr[index] = num
                  index += 1
  
          if simulation:
              iteration = iteration + 1
              print("iteration", iteration, ":", *arr)
  
          position *= 10
      return arr
      
new_contents: """
  radix sort
  complexity: O(nk + n) . n is the size of input list and k is the digit length of the number
  """
  def radix_sort(arr, simulation=False):
      position = 1
      max_number = max(arr)
  
      iteration = 0
      if simulation:
          print("iteration", iteration, ":", *arr)
  
      while position <= max_number:
          queue_list = [list() for _ in range(10)]
  
          for num in arr:
              digit_number = num // position % 10
              queue_list[digit_number].append(num)
  
          index = 0
          for numbers in queue_list:
              for num in numbers:
                  arr[index] = num
                  index += 1
  
          if simulation:
              iteration = iteration + 1
              print("iteration", iteration, ":", *arr)
  
          position *= 10
      return arr
      
subject: fix error if max_number is a multiple of 10 (#511)