Advent of Code 2015 Day 15 Part 1

Mix.install([
  {:kino_aoc, "~> 0.1"},
  {:nx, "~> 0.9.2"}
])

Get Inputs

{:ok, puzzle_input} =
  KinoAOC.download_puzzle("2015", "15", System.fetch_env!("LB_SESSION"))

My answer

Regex.named_captures(
  ~r/(?[a-zA-Z]+): .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+)/,
  "Butterscotch: capacity -1, durability -2, flavor 6, texture 3, calories 8"
)

get_ingredients_tensor = fn rows ->
  rows
  |> Enum.map(fn row ->
    Regex.named_captures(
      ~r/(?[a-zA-Z]+): .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+), .+ (?\-*\d+)/,
      row
    )
    |> then(fn %{"capacity" => capacity, "durability" => durability, "flavor" => flavor, "texture" => texture} ->
      [
        String.to_integer(capacity),
        String.to_integer(durability),
        String.to_integer(flavor),
        String.to_integer(texture)
      ]
    end)
  end)
  |> Nx.tensor()
end

ingredients =
  [
    "Butterscotch: capacity -1, durability -2, flavor 6, texture 3, calories 8",
    "Cinnamon: capacity 2, durability 3, flavor -2, texture -1, calories 3"
  ]
  |> get_ingredients_tensor.()

nums = Nx.tensor([[44, 56]])

Nx.dot(nums, ingredients)

nums
|> Nx.dot(ingredients)
|> Nx.product(axes: [1])

ingredients =
  puzzle_input
  |> String.split("\n")
  |> get_ingredients_tensor.()

all_combinations =
  for sprinkles <- 0..100,
      peanut_butter <- 0..100,
      frosting <- 0..100,
      sugar <- 0..100,
      sprinkles + peanut_butter + frosting + sugar == 100 do
    [sprinkles, peanut_butter, frosting, sugar]
  end

all_combinations
|> Nx.tensor()
|> Nx.dot(ingredients)

all_combinations
|> Nx.tensor()
|> Nx.dot(ingredients)
|> Nx.max(0)

all_combinations
|> Nx.tensor()
|> Nx.dot(ingredients)
|> Nx.max(0)
|> Nx.product(axes: [1])

all_combinations
|> Nx.tensor()
|> Nx.dot(ingredients)
|> Nx.max(0)
|> Nx.product(axes: [1])
|> Nx.reduce_max()