ynonp

defmodule Day9 do
  @preamble_length 25

  def read_input do
    File.read!("input/day9.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&String.to_integer/1)
  end

  def valid?(window, item) do

ynonp

defmodule VM do
  defstruct [:ip, :code, :acc]
end

defmodule Day8 do
  def read_input do
    File.read!("input/day8.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&(String.split(&1, " ", trim: true)))
    |> Enum.map(fn [action, param] -> { action, String.to_integer(param) } end)

ynonp

defmodule Rule do
  defstruct [:from, :to, :count]
end

defmodule Day7 do
  def read_input do
    File.read!("input/day7.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&(String.replace(&1, "bags", "bag")))
    |> Enum.map(&(String.trim(&1, ".")))

ynonp

defmodule Day6 do
  def read_input do
    File.read!("input/day6.txt")
    |> String.split("\n\n", trim: true)
  end

  def get_common_answers(str) do
    answers = String.split(str, "\n", trim: true)
              |> Enum.map(&String.graphemes/1)
              |> Enum.map(&(MapSet.new(&1)))

ynonp

defmodule Seat do
  defstruct min_row: 0, max_row: 127, min_col: 0, max_col: 7

  def from_string(str) do
    str
    |> String.graphemes
    |> Enum.reduce(%Seat{}, &Day5.process_letter/2)
  end

  def from_tuple({row, col}) do

ynonp

defmodule Day4 do
  def read_input do
    File.read!("input/day4.txt")
    |> String.split("\n\n", trim: true)
    |> Enum.map(&to_passport/1)
  end

  def to_passport(str) do
    str
    |> String.split(~r{\s+}, trim: true)

ynonp

defmodule Day3 do
  def read_input do
    File.read!("input/day3.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&String.graphemes/1)
    |> Enum.map(&Enum.with_index/1)
    |> Enum.with_index
    |> Enum.flat_map(fn {line, row} -> Enum.map(line, fn {el, col} -> {{row, col}, (if el == "#", do: 1, else: 0) } end) end)
    |> Enum.into(%{})
  end

ynonp

defmodule Day2 do
  def read_input do
    File.read!("input/day2.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&(Regex.scan(~r/(\d+)-(\d+) (\w+): (.*)/, &1)))
    |> Enum.map(fn [[_, min, max, char, text]] -> {
      String.to_integer(min),
      String.to_integer(max),
      char,
      text

ynonp

defmodule Day1 do
  def read_input do
    File.read!("input/day1.txt")
    |> String.split("\n", trim: true)
    |> Enum.map(&String.to_integer/1)
  end

  def part1 do
    values = read_input()
    for a <- values, b <- values, a + b == 2020, do: a * b

ynonp

text = "some string (with parentheses (and also inner parentheses)) (yay) hi"

stack = []
for i in range(len(text)):
    char = text[i]
    if char == "(":
        stack.append(char)
    elif char == ")":
        stack.pop()
        if len(stack) == 0: