chore: complete day 4

solutions/Days/Day04.hs

@@ -1,16 +1,30 @@
+{-# LANGUAGE OverloadedStrings #-}
+
 module Days.Day04 (day04) where
 
 import AOC (Solution (..))
-import qualified Data.Text as T
+import Data.Text qualified as T
 
 day04 :: Solution
 day04 = Solution parseInput part1 part2
 
-parseInput :: T.Text -> a
-parseInput = error "parseInput not defined for day 04"
+parseInput :: T.Text -> [[[Int]]]
+parseInput = map (map (map (read . T.unpack) . T.splitOn "-") . T.splitOn ",") . T.lines
 
-part1 :: a -> Int
-part1 = error "part1 not defined for day 04"
+part1 :: [[[Int]]] -> Int
+part1 input = sum $ map logic input
+  where
+    logic [[u1, u2], [d1, d2]]
+      | u1 >= d1 && u2 <= d2 = 1
+      | d1 >= u1 && d2 <= u2 = 1
+      | otherwise = 0
 
-part2 :: a -> Int
-part2 = error "part2 not defined for day 04"
+part2 :: [[[Int]]] -> Int
+part2 input = sum $ map logic input
+  where
+    logic [[u1, u2], [d1, d2]]
+      | u1 >= d1 && u1 <= d2 = 1
+      | u2 >= d1 && u2 <= d2 = 1
+      | d1 >= u1 && d1 <= u2 = 1
+      | d2 >= u1 && d2 <= u2 = 1
+      | otherwise = 0