defmodule Main do
  def main do
    IO.read(:line)
    |> String.trim()
    |> String.split()
    |> Enum.map(&String.to_integer/1)
    |> solve
    |> IO.puts()
  end

  def solve(rgb) do
    rgb |> solve_rec(0)
  end

  def solve_rec(rgb, x) do
    case rgb |> Enum.sort() do
      [0, 0, 0] -> x
      [0, 0, 1] -> x
      [0, 1, 1] -> x
      [0, b, c] -> [1, b, c - 2] |> solve_rec(x)
      [a, b, c] -> [0, b - a, c - a] |> solve_rec(x + a)
    end
  end
end