Copyright	(c) Eric Mertens 2022
License	ISC
Maintainer	emertens@gmail.com
Safe Haskell	None
Language	Haskell2010

Main

Description

>>> :set -XQuasiQuotes
>>> let input = parseInput "498,4 -> 498,6 -> 496,6\n503,4 -> 502,4 -> 502,9 -> 494,9\n"
>>> let world = Set.fromList (concatMap segs input)
>>> let limit = voidLimit world
>>> let Left world1 = fillFrom Left limit world top
>>> let picture = Data.Map.fromSet (const '█') world <> Data.Map.fromSet (const '◆') world1
>>> putStr (Advent.Coord.drawPicture picture)
······◆···
·····◆◆◆··
····█◆◆◆██
···◆█◆◆◆█·
··███◆◆◆█·
····◆◆◆◆█·
·◆·◆◆◆◆◆█·
█████████·
>>> Set.size world1 - Set.size world
24
>>> let Identity world2 = fillFrom Identity limit world top
>>> let picture = Data.Map.fromSet (const '█') world <> Data.Map.fromSet (const '◆') world2
>>> putStr (Advent.Coord.drawPicture picture)
··········◆··········
·········◆◆◆·········
········◆◆◆◆◆········
·······◆◆◆◆◆◆◆·······
······◆◆█◆◆◆██◆······
·····◆◆◆█◆◆◆█◆◆◆·····
····◆◆███◆◆◆█◆◆◆◆····
···◆◆◆◆·◆◆◆◆█◆◆◆◆◆···
··◆◆◆◆◆◆◆◆◆◆█◆◆◆◆◆◆··
·◆◆◆█████████◆◆◆◆◆◆◆·
◆◆◆◆◆·······◆◆◆◆◆◆◆◆◆
>>> Set.size world2 - Set.size world
93

Synopsis

parseInput :: String -> Input
getInput :: Int -> Int -> IO Input
type Input = [[(Int, Int)]]
main :: IO ()
top :: Coord
voidLimit :: Set Coord -> Int
fillFrom :: Monad m => (Set Coord -> m (Set Coord)) -> Int -> Set Coord -> Coord -> m (Set Coord)
segs :: [(Int, Int)] -> [Coord]
seg :: (Int, Int) -> (Int, Int) -> [Coord]

Documentation

parseInput :: String -> Input Source #

getInput :: Int -> Int -> IO Input Source #

type Input = [[(Int, Int)]] Source #

main :: IO () Source #

>>> :main
644
27324

top :: Coord Source #

The entry point of sand at 500,0

voidLimit :: Set Coord -> Int Source #

Find the level beyond any walls.

fillFrom Source #

Arguments

:: Monad m
=> (Set Coord -> m (Set Coord))	behavior when sand reaches limit
-> Int	lower limit
-> Set Coord	initial wall and sand locations
-> Coord	location to fill from
-> m (Set Coord)	final wall and sand locations

Fill the given world with sand from a fill coordinate returning the final state of the world. This is parameterized over a callback for how to handle when sand reaches the bottom of the level in order to allow early termination or not.

segs :: [(Int, Int)] -> [Coord] Source #

seg :: (Int, Int) -> (Int, Int) -> [Coord] Source #