X-Git-Url: https://git.njae.me.uk/?p=advent-of-code-20.git;a=blobdiff_plain;f=advent15%2Fsrc%2Fadvent15.hs;h=ac0f2b450129f73b1a45396dd13e3aa3fa70cfff;hp=87cbf3de8c38a443ed195335c403913e6af1edec;hb=de640d46282134bb95db645a2bd8de687f3251b1;hpb=4ecf3b3b78c6ae46bb41526085d69572ba1e9204

diff --git a/advent15/src/advent15.hs b/advent15/src/advent15.hs
index 87cbf3d..ac0f2b4 100644
--- a/advent15/src/advent15.hs
+++ b/advent15/src/advent15.hs
@@ -7,6 +7,9 @@ import Data.STRef
 import qualified Data.Vector.Unboxed.Mutable as V
 
 
+type STInt s = STRef s Int
+type VInt s = V.MVector s Int
+
 main :: IO ()
 main = 
   do  let seed = [20, 0, 1, 11, 6, 3]
@@ -18,24 +21,25 @@ main =
 part1 seed = runGame seed 2020
 part2 seed = runGame seed 30000000
 
-zeroInt :: Int
-zeroInt = 0
+runGame :: [Int] -> Int -> Int
+runGame seed roundsNeeded =
+  runST $ 
+    do (round, word, history) <- seedGame seed roundsNeeded
+       gameSteps roundsNeeded round word history
+       readSTRef word
 
+seedGame :: [Int] -> Int -> ST s (STInt s, STInt s,  VInt s)
 seedGame seed historySize = 
   do round <- newSTRef $ length seed
      word <- newSTRef $ last seed
-     history <- V.replicate historySize zeroInt
+     history <- V.replicate historySize 0
      forM_ (zip (init seed) [1..]) $ \(t, s) -> V.write history t s
      return (round, word, history)
 
-runGame seed roundsNeeded =
-  runST $ 
-    do (round, word, history) <- seedGame seed roundsNeeded
-       gameStep roundsNeeded round word history
-       readSTRef word
 
-gameStep :: Int -> STRef s Int -> STRef s Int -> V.MVector s Int -> ST s ()
-gameStep targetRound round word history =
+-- gameSteps :: Int -> STRef s Int -> STRef s Int -> V.MVector s Int -> ST s ()
+gameSteps :: Int -> STInt s -> STInt s -> VInt s -> ST s ()
+gameSteps targetRound round word history =
   do roundVal <- readSTRef round
      if roundVal == targetRound
      then return ()
@@ -46,7 +50,7 @@ gameStep targetRound round word history =
            V.write history wordVal roundVal
            modifySTRef round (+1)
            writeSTRef word word'
-           gameStep targetRound round word history
+           gameSteps targetRound round word history
 
 
 speakWord :: Int -> Int -> Int