defmodule Main do
  def main do
    num = IO.gets("") |> String.trim |> String.split |>Enum.map(&String.to_integer/1)
    check(num)
  end
  def check([a, b, c]) do
  [abs(a-b), abs(b-c), abs(c-a)] |> Enum.min |> IO.inspect
  end
end