2015 Day 02 in Haskell

2015/day02/day02.hs

@@ -0,0 +1,16 @@
+import Aoc
+import Data.List.Split
+
+parseFile :: [String] -> [(Int, Int, Int)]
+parseFile = map $ triplet . map read . splitOn "x"
+
+part1 :: [(Int, Int, Int)] -> Int
+part1 = sum . map wrapping
+    where wrapping (l, w, h) = let areas = [l*w, l*h, w*h] in 2*sum areas + minimum areas
+
+part2 :: [(Int, Int, Int)] -> Int
+part2 = sum . map wrapping
+    where wrapping (l, w, h) = 2*minimum [l+w, l+h, w+h] + l*w*h
+
+main :: IO ()
+main = aocMain parseFile part1 part2

aoc.hs

@@ -10,3 +10,12 @@ aocMain parseFile part1 part2 = do
 
 enumerate :: [a] -> [(Int, a)]
 enumerate xs = zip [0..length xs] xs
+
+unimplemented :: Show p => p -> Int
+unimplemented = error . show
+
+pair :: [a] -> (a, a)
+pair as = let [a1, a2] = as in (a1, a2)
+
+triplet :: [a] -> (a, a, a)
+triplet as = let [a1, a2, a3] = as in (a1, a2, a3)