6 hs

6.hs

@@ -0,0 +1,12 @@
+import Data.List
+import Data.List.Split
+
+readlines :: FilePath -> IO [String]
+readlines = fmap (splitOn "\n\n" . init) . readFile
+
+solution2 :: [[String]] -> Int
+solution2 = sum . (map $ length . foldr1 intersect)
+
+main = do
+    input <- readlines "6.txt"
+    print (solution2 $ map (splitOn "\n") input)