defmodule Main do
  def main do
    [n, _] =
      IO.read(:line)
      |> String.split()
      |> Enum.map(&String.to_integer/1)

    1..n
    |> Enum.map(fn _ ->
      IO.read(:line)
    end)
    |> Enum.join()
    |> String.to_charlist()
    |> Enum.count(&(&1 == ?W))
    |> IO.puts()
  end
end