Removed alternate solution for day 2; minor adjustments to day 5 alternate solution (Vector still slower than IntMap...)

2.hs

@@ -3,12 +3,6 @@
 import Data.List (find)
 import Data.Maybe (catMaybes)
 
-checksum :: [[Int]] -> Int
-checksum = sum . map (\line -> maximum line - minimum line)
-
-divsum :: [[Int]] -> Int
-divsum   = sum . map divline
-
 divline :: [Int] -> Int
 divline ns = 
     uncurry div . head . catMaybes . map (\x -> Just (x,) <*> find (greaterAndDivisible x) ns) $ ns
@@ -16,7 +10,6 @@ divline ns =
 
 main :: IO ()
 main = do
-    input <- readFile "2.txt"
-    let grid = map (map read . words) $ lines input :: [[Int]]
-    print $ checksum grid
-    print $ divsum   grid
+    grid <- fmap (map (map read . words) . lines) $ readFile "2.txt"
+    print $ sum . map (\line -> maximum line - minimum line) $ grid
+    print $ sum . map divline $ grid

2_alt.hs

@@ -1,28 +0,0 @@
-import Data.List
-
-checksum :: [[Int]] -> Int
-checksum = sum . map (\line -> maximum line - minimum line)
-
-divsum :: [[Int]] -> Int
-divsum = sum . map divline
-
-divline :: [Int] -> Int
-divline ns =
-    let (n, m) = catTupleMaybes $ map (\x -> (x, find (greaterAndDivisible x) ns)) ns
-    in  n `div` m
-    where
-        greaterAndDivisible :: Int -> Int -> Bool
-        greaterAndDivisible n m = n > m && n `mod` m == 0
-
-catTupleMaybes :: [(Int, Maybe Int)] -> (Int, Int)
-catTupleMaybes [] = (0, 1)
-catTupleMaybes ((t1, mt2):ts) = case mt2 of
-    Just t2 -> (t1, t2)
-    Nothing -> catTupleMaybes ts
-
-main :: IO ()
-main = do
-    input <- readFile "2.txt"
-    let grid = map (map read . words) $ lines input :: [[Int]]
-    print $ checksum grid
-    print $ divsum   grid

5_alt.hs

@@ -1,18 +1,13 @@
 import Data.Vector.Unboxed (Vector, fromList, (!), (//))
 import qualified Data.Vector.Unboxed as V (length)
 
-type Length = Int
-type Index = Int
-type Steps = Int
-type State = (Steps, Index, Vector Int)
+type State = (Int, Int, Vector Int)
 type Update = Int -> Int
 
 next :: Update -> State -> State
 next f (steps, i, jumps) =
     let value = jumps ! i
-        nextI = i + value
-        nextJumps = jumps // [(i, f value)]
-    in  (steps + 1, nextI, nextJumps)
+    in  (steps + 1, i + value, jumps // [(i, f value)])
 
 getExitSteps :: Update -> State -> Int
 getExitSteps f (steps, i, jumps) =
@@ -20,7 +15,6 @@ getExitSteps f (steps, i, jumps) =
 
 main :: IO ()
 main = do
-    input <- readFile "5.txt"
-    let jumpsList = fromList $ map read $ lines input
+    jumpsList <- fmap (fromList . map read . lines) $ readFile "5.txt"
     print $ getExitSteps (+1)                                    (0, 0, jumpsList)
     print $ getExitSteps (\v -> if v >= 3 then v - 1 else v + 1) (0, 0, jumpsList)