86 lines
1.7 KiB
Markdown
86 lines
1.7 KiB
Markdown
# AOC 2024 Day 22
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```elixir
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[{:kino_benchee, "~> 0.1.0"}] |> Mix.install
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```
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## Section
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```elixir
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input = """
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"""
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```
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## Section
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```elixir
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defmodule MonkeyMarket do
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@doc """
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## Example
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iex> MonkeyMarket.part2([1,2,3,2024])
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23
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"""
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def part2(input) do
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for m <- (
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for j <- input do
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diffs = MonkeyMarket.next(j, 2000)
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|> Stream.map(&rem(&1, 10))
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|> Enum.reverse()
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|> Stream.chunk_every(2, 1, :discard)
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|> Stream.map(fn [a,b] -> {b, b-a} end)
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for [_,_,_,{n,_}] = chunk <- diffs
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|> Stream.chunk_every(4, 1, :discard),
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chunk = chunk |> Enum.map(&(elem(&1, 1))),
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reduce: %{} do
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acc2 ->
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acc2 |> Map.update(chunk, n, &(&1))
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end
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end), reduce: %{} do
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acc -> Map.merge(
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m,
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acc,
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fn _, s1, s2 ->
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s1+s2
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end
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)
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end
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|> Enum.max_by(&elem(&1, 1))
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|> elem(1)
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end
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@doc """
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## Example
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iex> MonkeyMarket.part1([1,10,100,2024])
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37327623
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"""
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def part1(input) do
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input
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|> Stream.map(&hd(MonkeyMarket.next(&1, 2000)))
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|> Enum.sum()
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end
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def next(a) do
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a = a |> Bitwise.bsl(6) |> Bitwise.bxor(a) |> Bitwise.band(16777215)
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a = a |> Bitwise.bsr(5) |> Bitwise.bxor(a) |> Bitwise.band(16777215)
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a |> Bitwise.bsl(11) |> Bitwise.bxor(a) |> Bitwise.band(16777215)
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end
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def next(a, x) when is_integer(a), do: next([a], x)
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def next(a, 0), do: a
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def next([prev | _ ] = a, n), do: next([next(prev) | a], n - 1)
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end
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```
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```elixir
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Benchee.run(%{
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part1: fn -> MonkeyMarket.part1(input) end
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})
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```
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```elixir
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MonkeyMarket.part2(input)
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```
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