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|
containers =
File.stream!("inputs/day17.txt")
|> Stream.map(&String.trim/1)
|> Stream.filter(&(&1 != ""))
|> Enum.map(fn line ->
{num, ""} = Integer.parse(line)
num
end)
defmodule EggnogStorage do
use Agent
def start do
Agent.start_link(fn -> %{} end, name: __MODULE__)
end
def combinations(_containers, 0) do
[[]]
end
def combinations([], _remainingCapacity) do
[]
end
def combinations(containers, remainingCapacity) do
cached_value = Agent.get(__MODULE__, &Map.get(&1, {containers, remainingCapacity}))
if cached_value do
cached_value
else
[nextContainer | remainingContainers] = containers
combinationsWithThisContainer =
if nextContainer <= remainingCapacity do
Enum.map(
combinations(remainingContainers, remainingCapacity - nextContainer),
fn x -> [nextContainer | x] end
)
else
[]
end
combinationsWithoutThisContainer = combinations(remainingContainers, remainingCapacity)
result = combinationsWithThisContainer ++ combinationsWithoutThisContainer
Agent.update(__MODULE__, &Map.put(&1, {containers, remainingCapacity}, result))
result
end
end
end
{:ok, _} = EggnogStorage.start()
combinations = EggnogStorage.combinations(containers, 150)
IO.puts("Combinations: #{length(combinations)}")
frequencies = Enum.map(combinations, &length/1) |> Enum.frequencies()
dbg(frequencies)
|
