defmodule Main do
  def main do
    IO.read(:line)

    IO.read(:line)
    |> String.trim()
    |> String.split()
    |> Enum.map(&String.to_integer/1)
    |> solve()
    |> IO.puts()
  end

  def solve(p) do
    p
    |> Enum.map(&loli/1)
    |> Enum.sum()
    |> loli
  end

  def loli(n) do
    case n do
      0 -> 0
      _ -> n |> rem(9)
    end
  end
end