defmodule Main do
  def main do
    [year, month, day] = IO.gets("") |> String.trim |> String.split("/") |> Enum.map(&String.to_integer/1)
    {:ok, date} = Date.new(year, month, day)
    next_day = Date.add(date, 2) |> Date.to_string
    IO.puts Regex.replace(~r/-/, next_day, "/")
  end
end