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

  defp solve([v, m, r, l]) do
    [v, m |> div(r), l |> div(r + 1)]
    |> Enum.min()
  end
end