1 files changed, 6 insertions, 15 deletions

diff --git a/execs/Day05.hs b/execs/Day05.hs
index c018203..aae8f49 100644
--- a/execs/Day05.hs
+++ b/execs/Day05.hs
@@ -1,21 +1,12 @@
 module Main where
 
-data Direction = Upper | Lower
+import Data.Char (digitToInt)
 
-doHalf :: [Direction] -> (Int, Int) -> Int
-doHalf ls start = fst $ foldl fn start ls 
-    where fn (l, u) Lower = (l, (u+l) `div` 2)
-          fn (l, u) Upper = ((u+l) `div` 2 + 1, u)
-
-doValidate :: String -> Int
-doValidate s = row * 8 + col
-    where row = flip doHalf (0, 127) $ map readDir (take 7 s)
-          col = flip doHalf (0, 7) $ map readDir (drop 7 s)
-
-readDir :: Char -> Direction
-readDir c
-  | c `elem` "FL" = Lower
-  | otherwise = Upper
+doValidate = toInt . map readBin
+toInt = foldl (\a x -> a * 2 + digitToInt x) 0
+readBin 'F' = '0'
+readBin 'L' = '0'
+readBin _ = '1'
 
 main :: IO ()
 main = do