defmodule Main do
  def main do
    c =
      IO.gets("")
      |> String.trim()

    d =
      IO.gets("")
      |> String.trim()

    (c <> d)
    |> String.split("x")
    |> Enum.map(fn i -> String.length(i) end)
    |> Enum.max(fn -> 0 end)
    |> IO.puts()
  end
end