Part1 works

day12.hs

@@ -0,0 +1,45 @@
+import Data.List.Split
+import Data.List
+import Data.Char as Char
+import Linear.V3
+
+main = do
+      moons <- map createMoon <$> map getList <$> map cleanString <$> lines <$> getContents
+      let newMoons = stepMoons moons 1000
+      let ernergy = sum $ map getErnergy newMoons
+      mapM putStrLn ( map show newMoons )
+      putStrLn ( show ernergy)
+
+data Moon = Moon{ position :: V3 Int
+                  ,velocity :: V3 Int
+                } deriving Show
+
+getList :: String -> [Int]
+getList = map read . splitOn ", "
+
+cleanString :: String -> String
+cleanString xs = xs \\ "<>xyz==="
+
+createMoon :: [Int] -> Moon
+createMoon [x,y,z] = Moon (V3 x y z) (V3 0 0 0)
+
+stepGravity :: [Moon] -> [Moon]
+stepGravity xs = map (\(p,v) -> Moon p v) $ zip (newPos) newVel
+            where newVel = zipWith (+) (getVel xs) (gravity $ getPos xs)
+                  newPos = zipWith (+) (getPos xs) (newVel)  
+
+getPos :: [Moon] -> [V3 Int]
+getPos xs = map(\x -> position x) xs
+
+getVel :: [Moon] -> [V3 Int]
+getVel xs = map(\x -> velocity x) xs
+
+gravity :: [V3 Int] -> [V3 Int]
+gravity xs = [sum [signum $ x-y | x<-xs, y/=x] | y<-xs]
+
+stepMoons :: [Moon] -> Int -> [Moon]
+stepMoons xs 0 = xs
+stepMoons xs n = stepMoons (stepGravity xs) (n-1)
+
+getErnergy :: Moon -> Int
+getErnergy (Moon pos vel)  = (sum $ abs pos) * (sum $ abs vel)