Files
AoC2022/day6.hs
Amneesh Singh 53ad5c4a8c day6
Signed-off-by: Amneesh Singh <natto@weirdnatto.in>
2022-12-06 10:59:06 +05:30

26 lines
525 B
Haskell

import Data.List (nub)
import Text.ParserCombinators.ReadP
main :: IO ()
main = do
input <- readFile "day6.in"
putStr "Q1: "
print $ q1 input
putStr "Q2: "
print $ q2 input
q1, q2 :: String -> Int
q1 = length . parse 4
q2 = length . parse 14
parse :: Int -> String -> String
parse n a = parse' n (splitAt n a)
parse' :: Int -> (String, String) -> String
parse' n (a, b)
| length (nub (drop (length a - n) a)) == n = a
| otherwise =
let (c, cs) = last $ readP_to_S get b
in parse' n (a ++ [c], cs)