Advent of code day 10

Mix.install([
  {:kino, "~> 0.5.0"}
])

Setup input

input = Kino.Input.textarea("Please paste your input file:")

p2 =
  input
  |> Kino.Input.read()

input =
  input
  |> Kino.Input.read()
  |> String.split(["\n"])

Common

defmodule Recur do
  def solve(command), do: solve(command, %{}, 1, 1)
  defp solve([], state, _, _machine_value), do: state

  defp solve(["noop" | commands], state, cycles, machine_value) do
    updated_state =
      0..1
      |> Enum.reduce(state, fn index, state ->
        Map.put(state, index + cycles, machine_value)
      end)

    solve(commands, updated_state, cycles + 1, machine_value)
  end

  defp solve([cur_command | commands], state, cycles, machine_value) do
    [_, value | _] = String.split(cur_command, " ")
    value = String.to_integer(value)

    state = Map.put(state, cycles, machine_value)
    state = Map.put(state, cycles + 1, machine_value)
    state = Map.put(state, cycles + 2, machine_value + value)

    solve(
      commands,
      state,
      cycles + 2,
      machine_value + value
    )
  end
end

Part 01

map = Recur.solve(input)

[20, 60, 100, 140, 180, 220] |> Enum.map(fn el -> el * map[el] end) |> Enum.sum()

Part 02

0..(map_size(map) - 2)
|> Enum.reduce("", fn cycle, render ->
  sprite_pos = map[cycle + 1]
  cycle = rem(cycle, 40)

  case {cycle == 0, abs(cycle - sprite_pos) < 2} do
    {true, true} -> render <> "\n" <> "#"
    {true, false} -> render <> "\n" <> "."
    {false, true} -> render <> "#"
    {false, false} -> render <> "."
  end
end)
|> IO.puts()