defmodule Main do
  def main, do: IO.read(:line) |> solve |> IO.puts()

  def solve(s) do
    {x, op_and_y} = s |> Integer.parse()
    {op, y_str} = op_and_y |> String.split_at(1)
    {y, _} = y_str |> Integer.parse()

    case op do
      "+" -> x - y
      "-" -> x + y
    end
  end
end