day 3: rewrite

use Data.Text

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

day3.hs

@@ -1,24 +1,28 @@
 import Data.Char (isAsciiLower, isAsciiUpper)
 import Data.List (intersect)
+import Data.Text (Text)
+import qualified Data.Text as T (foldl, lines, splitAt)
+import Lib (readFile')
 
 main :: IO ()
 main = do
-  input <- lines <$> readFile "day3.in"
+  input <- map parse . T.lines <$> readFile' "day3.in"
   putStr "Q1: "
   print $ q1 input
   putStr "Q2: "
   print $ q2 input
 
-q1 :: [String] -> Int
+q1 :: [[Int]] -> Int
-q1 =
+q1 = sum . map (\x -> head . uncurry intersect $ splitAt (div (length x) 2) x)
-  sum
-    . map (\x -> val . head . uncurry intersect $ splitAt (div (length x) 2) x)
 
-q2 :: [String] -> Int
+q2 :: [[Int]] -> Int
 q2 [] = 0
 q2 input =
   let (cur, rest) = splitAt 3 input
-   in (val . head . foldr1 intersect) cur + q2 rest
+   in (head . foldr1 intersect) cur + q2 rest
+
+parse :: Text -> [Int]
+parse = T.foldl (\xs x -> val x : xs) []
 
 val :: Char -> Int
 val c