solve 2022 day 2 part 2

2022/src/Aoc/Day2.hs

@@ -1,23 +1,48 @@
 module Aoc.Day2 (solve) where
 
-solve 1 input = sum $ map scoreGame guide
+parseInput :: String -> [[String]]
+parseInput = map words . lines
+
+-- A: rock, B: paper, C: scissors
+scoreGame :: [String] -> Integer
+scoreGame ["A", "A"] = 1 + 3
+scoreGame ["A", "B"] = 2 + 6
+scoreGame ["A", "C"] = 3 + 0
+scoreGame ["B", "A"] = 1 + 0
+scoreGame ["B", "B"] = 2 + 3
+scoreGame ["B", "C"] = 3 + 6
+scoreGame ["C", "A"] = 1 + 6
+scoreGame ["C", "B"] = 2 + 0
+scoreGame ["C", "C"] = 3 + 3
+scoreGame _          = 0
+
+totalScore :: [[String]] -> Integer
+totalScore = sum . map scoreGame
+
+solve :: Integer -> String -> Integer
+solve 1 input = totalScore games
   where
-    guide = map words . lines $ input
+    games = map convertGuide $ parseInput input
 
-    loss = 0
-    draw = 3
-    win  = 6
+    convertGuide [p, "X"] = [p, "A"]
+    convertGuide [p, "Y"] = [p, "B"]
+    convertGuide [p, "Z"] = [p, "C"]
+    convertGuide xs       = xs
 
-    rock     = 1
-    paper    = 2
-    scissors = 3
+solve 2 input = totalScore games
+  where
+    games = map solveGuide $ parseInput input
 
-    scoreGame ["A", "X"] = rock + draw
-    scoreGame ["A", "Y"] = paper + win
-    scoreGame ["A", "Z"] = scissors + loss
-    scoreGame ["B", "X"] = rock + loss
-    scoreGame ["B", "Y"] = paper + draw
-    scoreGame ["B", "Z"] = scissors + win
-    scoreGame ["C", "X"] = rock + win
-    scoreGame ["C", "Y"] = paper + loss
-    scoreGame ["C", "Z"] = scissors + draw
+    -- X: loss, Y: draw, Z: win
+    solveGuide ["A", "X"] = ["A", "C"]
+    solveGuide ["A", "Y"] = ["A", "A"]
+    solveGuide ["A", "Z"] = ["A", "B"]
+    solveGuide ["B", "X"] = ["B", "A"]
+    solveGuide ["B", "Y"] = ["B", "B"]
+    solveGuide ["B", "Z"] = ["B", "C"]
+    solveGuide ["C", "X"] = ["C", "B"]
+    solveGuide ["C", "Y"] = ["C", "C"]
+    solveGuide ["C", "Z"] = ["C", "A"]
+    solveGuide xs         = xs
+
+solve _ _ = 0