fileContents = File.read!("inputs/day25.txt")

[row, column] =
  Regex.run(~r/Enter the code at row (\d+), column (\d+)./, fileContents, capture: :all_but_first)
  |> Enum.map(fn num ->
    {num, ""} = Integer.parse(num)
    num
  end)

codes = Stream.iterate(20_151_125, &rem(&1 * 252_533, 33_554_393))

indices =
  Stream.iterate({1, 1}, fn
    {1, col} -> {col + 1, 1}
    {row, col} -> {row - 1, col + 1}
  end)

{{^row, ^column}, code} =
  Stream.zip(indices, codes)
  |> Enum.find(fn
    {{^row, ^column}, _} -> true
    _ -> false
  end)

IO.puts("Code: #{code}")