Day 3

Day3/puzzle1.hs

@@ -0,0 +1,12 @@
+import Data.List.Split (splitOn)
+import Data.Char (isDigit)
+import Text.Regex.TDFA (getAllTextMatches, (=~))
+
+sumMul :: [String] -> Int
+sumMul xs = let vals = map (splitOn "," . filter (`elem` "0123456789,")) xs
+            in  sum $ map (product . map read) vals
+
+main = do
+    contents <- readFile "day3.txt"
+    let mults = getAllTextMatches (contents =~ "mul\\([0-9]+,[0-9]+\\)") :: [String]
+    print $ sumMul mults