defmodule Main do
  def main do
    IO.read(:line)
    |> String.trim()
    |> String.to_integer()
    |> interact()
    |> IO.puts()
  end

  def interact(n) do
    interact_rec(1..n |> Enum.to_list())
  end

  def interact_rec(r) do
    search_unnecessary(0..((r |> length) - 1) |> Enum.to_list, r)
  end

  def search_unnecessary([], r) do
    "! #{r |> length}\n#{r |> Enum.join(" ")}\n"
  end

  def search_unnecessary([h | t], r) do
    s = r |> List.delete_at(h)

    cond do
      IO.gets("? #{(r |> length) - 1}\n#{s |> Enum.join(" ")}\n") |> String.trim() == "1" ->
        interact_rec(s)

      true ->
        search_unnecessary(t, r)
    end
  end
end