Day Six

Mix.install([
  {:kino, "~> 0.7.0"}
])

Section

input = Kino.Input.textarea("Input")

defmodule DaySix do
  def solve1(input) do
    list = String.to_charlist(input)

    Enum.zip([list, Enum.drop(list, 1), Enum.drop(list, 2), Enum.drop(list, 3)])
    |> Enum.find_index(fn {a, b, c, d} ->
      MapSet.size(MapSet.new([a, b, c, d])) == 4
    end)
    |> then(fn i -> i + 4 end)
  end

  def solve2(input) do
    list = String.to_charlist(input)

    0..13
    |> Enum.map(fn i -> Enum.drop(list, i) end)
    |> Enum.zip()
    |> Enum.find_index(fn vs ->
      vs
      |> Tuple.to_list()
      |> MapSet.new()
      |> MapSet.size()
      |> then(&(&1 == 14))
    end)
    |> then(&(&1 + 14))
  end
end

DaySix.solve2(Kino.Input.read(input))