[hs] Solve 2020_06

hs/src/Aoc/Y2020/D06.hs

@@ -0,0 +1,25 @@
+module Aoc.Y2020.D06
+  ( day
+  ) where
+
+import qualified Data.Set  as Set
+
+import           Aoc.Day
+import           Aoc.Parse
+
+type Group = [String]
+
+parser :: Parser [Group]
+parser = sepBy (endBy1 (some lowerChar) newline) newline
+
+solver :: [Group] -> IO ()
+solver groups = do
+  putStrLn ">> Part 1"
+  print $ sum $ map (Set.size . foldr1 Set.union . map Set.fromList) groups
+
+  putStrLn ""
+  putStrLn ">> Part 2"
+  print $ sum $ map (Set.size . foldr1 Set.intersection . map Set.fromList) groups
+
+day :: Day
+day = dayParse "2020_06" parser solver