Day 04

1 files changed, 18 insertions, 0 deletions

diff --git a/utils.hs b/utils.hs
index 33f3f6e..04211ea 100644
--- a/utils.hs
+++ b/utils.hs
@@ -1,7 +1,25 @@
 module Utils where
 
+import Control.Applicative (ZipList (ZipList, getZipList))
+
 (.>) = flip (.)
 
 ($>) = flip ($)
 
 infixr 6 $>
+
+splitOn :: (Char -> Bool) -> String -> [String]
+splitOn p s = case dropWhile p s of
+  "" -> []
+  s' -> w : splitOn p s''
+    where
+      (w, s'') = break p s'
+
+transpose :: [[a]] -> [[a]]
+transpose = getZipList . traverse ZipList
+
+mapWithIndex :: (Num a1, Enum a1) => (a2 -> b) -> [a2] -> [(a1, b)]
+mapWithIndex f xs = zip [0 ..] (map f xs)
+
+removeAt :: [Int] -> [b] -> [b]
+removeAt is xs = mapWithIndex id xs $> filter (\(i', _) -> i' `notElem` is) .> map snd