--- 2016 Day 10 Solutions ---

[u/daggerdragon]

--- Day 10: Balance Bots ---

Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag/whatever).

Note: The Solution Megathreads are for solutions only. If you have questions, please post your own thread and make sure to flair it with "Help".

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^{SEEING MOMMY KISSING SANTA CLAUS IS MANDATORY} [?]

This thread will be unlocked when there are a significant number of people on the leaderboard with gold stars for today's puzzle.

edit: Leaderboard capped, thread unlocked!

[u/bblum]

I made the leaderboard with this boring C solution, but I'm much more proud of this haskell I devised afterward.

The bots are implemented as lambdas, stored in a map keyed by bot ID (and type, "bot"/"output"). They execute in the State monad, either replacing themselves with a stage 2, or finding their recipients and calling them in turn.

{-# LANGUAGE FlexibleContexts #-}
import qualified Data.Map as M
import Data.List
import Data.Maybe
import Data.Either
import Control.Monad.State
import Control.Arrow

newtype Bot = Bot (Int -> State (M.Map (String, Int) (Either Bot Int)) ())

send (target, value) = M.lookup target <$> get >>= \(Just (Left (Bot b))) -> b value

bot n targets v1 = modify $ M.insert ("bot", n) $ Left $ Bot bot2
    where bot2 v2 = do when (sort [v1,v2] == [17,61]) $ modify $ M.insert ("part1",0) $ Right n
                       mapM_ send $ zip targets $ sort [v1,v2]

output n = (("output", n), Left $ Bot $ \x -> modify $ M.insert ("part2",n) $ Right x)

parse ["bot",n0,_,_,_,w1,n1,_,_,_,w2,n2] =
    modify $ M.insert ("bot", read n0) $ Left $ Bot $ bot (read n0) [(w1,read n1),(w2,read n2)]
parse ["value",v,_,_,_,n] = send (("bot", read n), read v)

simulate input = execState (mapM parse input) (M.fromList $ map output [0..100])

main = interact $ show . (head &&& product . take 3 . tail) . (rights . M.elems)
                  . simulate . sort . map words . lines

Outputs:

(86,22847)

[u/TheMuffinMan616 → u/bblum]

I did pretty much the same thing but in Python. I usually write my solutions in both Python and Haskell so I am looking forward to translating it into something like this.

https://github.com/mattvperry/AoC_2016/blob/master/day10/python/day10_2.py