From 1a0e96e2a82d8d0a7d595f37d68a67f81206d46b Mon Sep 17 00:00:00 2001
From: Felix Valentini <felixvalentini@Felixs-MBP.fritz.box>
Date: Tue, 6 Dec 2022 22:43:46 +0100
Subject: [PATCH] solved part 2 of day 6
---
6/solve.hs | 27 ++++++++++++++++++++++-----
1 file changed, 22 insertions(+), 5 deletions(-)
diff --git a/6/solve.hs b/6/solve.hs
index d414bed..14656fd 100644
--- a/6/solve.hs
+++ b/6/solve.hs
@@ -5,6 +5,9 @@ type EnumeratedChar = (Int, Char)
sample :: String
sample = "mjqjpqmgbljsphdztnvjfqwrcgsmlb"
+sample1 :: String
+sample1 = "nppdvjthqldpwncqszvftbrmjlhg"
+
allDifferent :: (Eq a) => [a] -> Bool
allDifferent [] = True
allDifferent (x:xs) = x `notElem` xs && allDifferent xs
@@ -13,23 +16,37 @@ takeLeftRight :: Int -> [a] -> ([a], [a])
takeLeftRight n = taking . splitAt n
where taking (left, right) = (take 4 $ reverse left, take 4 right)
+takeLeftRight' :: Int -> [a] -> ([a], [a])
+takeLeftRight' n = taking . splitAt n
+ where taking (left, right) = (take 14 $ reverse left, take 14 right)
+
checkForMarker :: [EnumeratedChar] -> Int
checkForMarker l = if (length $ getString l) < 4
then 0
else
if allDifferent $ getString l
then fst $ head l
- else 0
+ else
+ if allDifferent $ getString $ reverse l
+ then fst $ head $ reverse l
+ else 0
evalTuple :: ([EnumeratedChar], [EnumeratedChar]) -> (Int, Int)
-evalTuple (x1, x2) = (checkForMarker $ reverse x1, checkForMarker x2) -- need to reverse it back somehow
+evalTuple (x1, x2) = (checkForMarker x1, checkForMarker x2)
getString :: [(Int, Char)] -> String
getString = snd . unzip
-solve :: String -> Int
-solve s = fst $ head $ filter (\(x, y) -> x > 0 && y > 0) $ map (\x -> evalTuple $ takeLeftRight x i) [1..(length s)-1]
+solve1 :: String -> Int
+solve1 s = fst $ head $ filter (\(x, _) -> x > 0) $ map (\x -> evalTuple $ takeLeftRight x i) [1..(length s)-1]
+ where i = zip [1..] s
+
+solve2 :: String -> Int
+solve2 s = fst $ head $ filter (\(x, _) -> x > 0) $ map (\x -> evalTuple $ takeLeftRight' x i) [1..(length s)-1]
where i = zip [1..] s
main :: IO ()
-main = readFile "./input.txt" >>= print . solve . head . lines
+main = do
+ input <- head <$> lines <$> readFile "./input.txt"
+ print $ solve1 input
+ print $ solve2 input
--
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