defmodule BinaryBoarding do
  def parse(input) do
    input
    |> String.replace(~r/[F|L]/, "0")
    |> String.replace(~r/[B|R]/, "1")
    |> String.split_at(7)
    |> Tuple.to_list()
    |> Enum.map(&String.to_integer(&1, 2))
  end
  def calc_id([row, column]) do
    row * 8 + column
  end
end
boarding_passes =
  File.read!("input")
  |> String.split("\n", trim: true)
  |> Enum.map(&BinaryBoarding.parse/1)
seats =
  boarding_passes
  |> Enum.map(&BinaryBoarding.calc_id/1)
IO.inspect(seats)
holes =
  for row <- 0..127,
      column <- 0..7,
      BinaryBoarding.calc_id([row, column]) <= 955 do
    seat = BinaryBoarding.calc_id([row, column])
    # IO.inspect(row, label: "row")
    # IO.inspect(column, label: "column")
    # IO.inspect(seat, label: "seat")
    if Enum.member?(seats, seat) do
      # IO.inspect(seat, label: "MEMBER")
    else
      IO.inspect(seat, label: "NOT MEMBER")
    end
  end
IO.inspect(holes)
holes |> Enum.max() |> IO.inspect()