7 files changed, 198 insertions, 21 deletions

diff --git a/aoc.cabal b/aoc.cabal
index bcb8d8c..cd5d039 100644
--- a/aoc.cabal
+++ b/aoc.cabal
@@ -19,8 +19,8 @@ extra-source-files:  CHANGELOG.md
 library 
   hs-source-dirs:      lib
   default-language:    Haskell2010
-  build-depends:       base
-  exposed-modules: Utils
+  build-depends:       base, containers
+  exposed-modules:     Utils
 
 executable Day01
   main-is:             Day01.hs
@@ -81,3 +81,9 @@ executable Day10
   build-depends:       base, aoc, containers, monad-memo
   default-language:    Haskell2010
   hs-source-dirs:      execs
+
+executable Day11
+  main-is:             Day11.hs
+  build-depends:       base, aoc, containers
+  default-language:    Haskell2010
+  hs-source-dirs:      execs
diff --git a/execs/Day10.hs b/execs/Day10.hs
index c42a550..40d3d61 100644
--- a/execs/Day10.hs
+++ b/execs/Day10.hs
@@ -16,9 +16,7 @@ diffs s = product $ ($ q s) <$> [howMany (==1), howMany (==3)]
 combos top s = startEvalMemo $ go 0
     where go c
             | c == top = return 1
-            | otherwise = do
-                let cs = filter (`elem` s) $ map (+c) [1,2,3]
-                sum <$> mapM (memo go) cs
+            | otherwise = sum <$> mapM (memo go) (filter (`elem` s) $ map (+c) [1,2,3])
 
 main :: IO ()
 main = do
diff --git a/execs/Day11.hs b/execs/Day11.hs
new file mode 100644
index 0000000..e2f138b
--- /dev/null
+++ b/execs/Day11.hs
@@ -0,0 +1,48 @@
+module Main where
+
+import Utils
+import Data.List (sortOn)
+import Data.Map (Map, (!))
+import qualified Data.Map as Map
+import Data.Maybe
+
+dirs = [ (-1,-1), (0,-1), (1,-1)
+       , (-1, 0),         (1, 0)
+       , (-1, 1), (0, 1), (1, 1)
+       ]
+
+adjs1 m pt = howMany (== '#') $ mapMaybe ((`Map.lookup` m) . add pt) dirs
+
+inGrid (x, y) w h = x < w && x >= 0 && y < h && y >= 0
+adjs2 grid pt w h = howMany ((== '#') . head)
+                        $ filter (not . null)
+                        $ map (dropWhile (== '.')
+                                . map (grid !)
+                                . takeWhile (inside (0, 0) (w-1, h-1))
+                                . map ($ pt)
+                                . repeatF
+                                . add)
+                     dirs
+
+rule1 w h m pt@(x, y) = if as == 0 then '#' else 'L'
+    where as = adjs2 m pt w h
+
+rule2 w h m pt@(x, y) = if as >= 5 then 'L' else '#'
+    where as = adjs2 m pt w h
+
+doStep w h m = Map.mapWithKey fn m
+    where fn k 'L' = rule1 w h m k
+          fn k '#' = rule2 w h m k
+          fn k '.' = '.'
+
+stepWhile prev w h
+  | prev == next = next
+  | otherwise = stepWhile next w h
+  where next = doStep w h prev
+
+main :: IO ()
+main = do
+    n <- readFile "input/11"
+    let (grid, width, height) = makeGrid n
+    let solve1 = stepWhile grid width height
+    print $ howMany ((== '#') . snd) $ Map.toList solve1
diff --git a/input/11 b/input/11
new file mode 100644
index 0000000..5a109fd
--- /dev/null
+++ b/input/11
@@ -0,0 +1,94 @@
+LLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LL.L.LLLL.LLLLLLLLL.LLLLL
+LLLLLLLL.LLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLLLLLLL.LLLLLLLLLL
+LLLLLLLLLLLLLLLLL.LLLLL.L.LLLLLL..LLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLL.LLLL.LLLL.LLLLL
+LLL.LL.LLLLLLLLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLLLLLLL.LLLLLL..LL
+LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.LLLL.LL.LLLLLLLLL.LLLLLLLLL..LLLL
+LLLLLLLLLLL..LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLL.LLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLL..LL..LLLL.LLLLLLLLLLLLLLLLLLLLLL.LLLL.LLLLL
+LLLLLLLLLLLLLLLLL.LLL.L.LLLLLLLL.LLLLLLLLL.LLLL.LLLL..LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLL
+.L........L.L.....L.L........LL...LLL....L.LL..LL..LL..LLLL.LL...........LL.LL..L..LL....L.L
+LLLLLL.LLLLL.LLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL..LLLLLL.LLLL.LLLL.LLLLLLLLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLL.LLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLL.L..LLLLLLLLL.LLLLLLLLLLL.LLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLLL.LLL.LLLLLLLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLL.LL.LLL.LLLLL.LLLLL.LLLLLLL.LLLLLLLLLLL.LL.LLLL.LLLLL
+LLLLLL.LLLLLLLLLL.LLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
+LLLLLL.LLLLLLLLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLL.LLLLLLLLL.LLLL.LLLLL.LLLL
+.............LLL...LL...L...LL...L...LL..........L.LLLLLL..L.L..L..LL..LLL.......L......L...
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLL..LLLLLLLLL.LLLLLLLLL.LLL.LLLL.LLLLLLLLL.LLLL.LLLLL
+LLLLLLLLLLLL.L.LLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLL.
+LLLLLLLLLLLL.LLLLLLLLLL.LLLLLLLLLLLLLLLLLLLL.LL.LLLL.LLLLLLLLLLLLL.LLLL.LLLLLLLLL.LLLLLLLLLL
+LLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLL.LLLLLL.LL.LLLLLLLLL.LLLLL.LLLL.LL.LLLL.LLLLLLLLL.LLLLLLLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLL.LLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLLLLLLL.LLLL.LLLLL
+LL...L.L....LL..L.........L...L....LLL......L.L..L..L...L........L..LLL.....L.LL.LL..LL..L..
+LLLLLL.LLLLL.LLLLL.LLLL.LL.LLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLL.LLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLLLLLLLL.LLLL.LLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLL.LLLL.LLLL.LLLLLLLLLLLLLLL
+LLLLLL.LLLLLLLLLL.LLLLLLLLLLLLLL.LLLLLLLLL.LL.LLLLLL.LLL.L.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LL.LL.LLLLLLL.LLLL.LLLLLLLLL..LLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLL.L.LLLLLLL.LLLLLLLLLLLLLL.LLLL.LLLLL
+...L.....L.L....L.LL...L..LLLL.L...L..L......L...L.L.L...L..L...LL.....L.L..L..L.L.L.....L..
+LLLLLL.LLLLL.LLLL.LLL..LLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+.LLLLL.LLLLL.LLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLLLLLLL.LLLLLLLLLL
+LLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LL.LLLL.LLLL.LLLL.LLLL.LLLL.L.LLL
+LLLLLL.LLLLLLLLLLLLLLLL.L.LLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.L.LLLLLLLLLLLLLLL.LLLL..LLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLL..LLLL.LLLLLLL.LLLL.LLLLLLLLL.LLLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLLLLLLLLL.LLLLL
+LLLLLL.LLLLLLLLL..LLLLLLLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLL.LLLLLLLLLLLL.LLLL.LLLLLLLLL.LLLLL
+LLLLLLLLLLLL.LLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLL.LLLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLLLLLL.L
+LL.L...LL....L..L.L..LL.....L.......L.LL...L.LLLL..L...............L.L..L.L...L..L..L..L....
+LLLLLL.LLLLLLLLLL.L.LLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLL..LLLLLLLLL.LL..L.LLLLLLL.LLLL.LLLL.LLLL.LLLL..LLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLL.LLLLLL.LLLLLLL.LLLL.LLLL.LLLLLLLLLLLLLLL
+LLLLLL.LLLLL.LLLLLLLLLL.LLL.LLLL.LLLLL.LLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLL.LLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLL.LLLL.L.LLLL.LLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLLLLLLLL
+.LL...LL...L...L..L..........L..L.L..L...LL......LL......L.......LL.LL..L...LLL.......LLLL..
+LLLLLLLLLLLL.LLLL.LLLLLLL.LLLLLL.LLLLLLLLL.LLLLLLLL...LLLL.LLLLLLL.LLLL..LLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LL.L..LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLLLLLLL..LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLLLLLLL.LLLLL
+LLLLLL.L.LLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLLLL.L.LLLL.LLLLLLLLL.LL.LLLLLLL
+LLLLLL.LLLL..LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLL.L.LLLLL..LLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLL.L.LLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLL..LLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LL.LL.LLLLLLLLLLL.LLLL.L.LLLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLL.LL.LL
+LLLLLL..LLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+.L.........L.L...L.....L..LL..LLL.L........L.LL.....L...L.....LL.....LLL....LLLL.L.L......L.
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLL.L.LL.LLLLLLLLL.LLLLLLLLLL
+LLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLLLLLLLLL.LLL.L
+LLLLLL.LLLLL.LLLLLLLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLLLLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLLLLLLLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLLLLLLL.LLLLLLLLLL
+....LL.L..L....L..L.L.....L...L..LL....LLL..L.....L.L.....L.LL...L.LLL.LL.....LL..LLL....L.L
+LLLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+.LLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL..LLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLL
+LLLLLLLL.LLL.LLLLLLL.LL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLL..LLLLLLLLLL
+LLLLLLLLLLLL.LLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL
+..L...LL.L.......L..L...L.L.L..L.L.LL...L....LLL.....L.......L...LL......L.LL...L.L...L.....
+LLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLLLLLLLLLLLL.LL.LLLLLLLLLLLL.LLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLLLLLLLLL.LL.LLLLLLLLLLLLLLL.LL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLL.LLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLLLLLLL.LLLL.LLLLL
+LLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLLLLL.L.LLLLL
+LLLLLL..LLLL.LLLL.LLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLL.L.LLLLL.LLLLLLL.LLLLLLLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLLLLL.LLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LL.LLL.LLLLL.LLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLL.LL.L.LLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+..L..L..LL..L...L....L.....LL.....LL..........L...L.L....L.........L......LL.....L.LL...LL..
+LLLLLL.LLLLL.LLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLL.LLL..LLLLL
+LLLLLL.L.LLLLLLLL.LLLL..LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLLLLLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLLL
+LLLLLL.LLLLLLLLLL.LLLL..LLLLLLLLLLLLLLLLLL.LL.LLLLLL.LLLLL.LLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLLLLL.LLLL.LLLLLLLLL.LLLLL
+LLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLLLLLL.L.LLL.LLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLLLLLLL
+LLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLLL
+.LL.L.L.L.LL.....L.L.LL....L..L.............L...L.L...LLL.LL.L..L........L.....L.LL..L..L...
+LLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLLLLLLLL.LLLLL.L.LLLLLLLLL.LLLL.LLLLLLLLLL
+LLLLLL.LLLLL.LL.LLL.LLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLL.L.LLLLLLL.LLLLL
+L.LLLL.LL.LL.LLLL.LLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LLLLLL.LLLLLLLLLL.LLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLLLL.LLLL..LLLL
+LLLLLL.LLLLLLLLLL.LLLLL.LLLLLLLL.LLLLLLLLL.LLLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLLLLL.L.LLLLL
+LLLLLL.LLLLL.LLLLLLLLLL.LLLLLLLL.LLLLLLLL.LLLLLLLLLL.LLLLLLLLLLLLL.LLLL.LLLL.LLLL.LLLL.LLLLL
+LL.LLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LLLLLLLLL..LLLLLLLL.LLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLL
+LLLLLL.LLLLL.LLLL.LLLLL.L.LLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLL.LLLLLLLLLLLLLLL
+LLLLLLLLLLLL.LLLL.LLLLL.LLLLLLLL.LL.LLLLLLL.LLLLLLLL.LLLLL.LLLLLLLLLLLL.LLLL.LLLLLLLLL.LLLLL
diff --git a/input/11sample b/input/11sample
new file mode 100644
index 0000000..1beaede
--- /dev/null
+++ b/input/11sample
@@ -0,0 +1,10 @@
+L.LL.LL.LL
+LLLLLLL.LL
+L.L.L..L..
+LLLL.LL.LL
+L.LL.LL.LL
+L.LLLLL.LL
+..L.L.....
+LLLLLLLLLL
+L.LLLLLL.L
+L.LLLLL.LL
diff --git a/input/11sample2 b/input/11sample2
new file mode 100644
index 0000000..a486e35
--- /dev/null
+++ b/input/11sample2
@@ -0,0 +1,9 @@
+.......#.
+...#.....
+.#.......
+.........
+..#L....#
+....#....
+.........
+#........
+...#.....
diff --git a/lib/Utils.hs b/lib/Utils.hs
index 61c4e49..6358230 100644
--- a/lib/Utils.hs
+++ b/lib/Utils.hs
@@ -1,19 +1,11 @@
-module Utils ( binaryToInt
-             , countElem
-             , xor
-             , right
-             , bet
-             , (&+)
-             , howMany
-             , sublists
-             , windows
-             ) where 
-
-import Data.Char (digitToInt)
-import Control.Monad
-import Data.Either
-import Data.List (inits, tails)
+module Utils where 
 
+import           Data.Char (digitToInt)
+import           Control.Monad
+import           Data.Either
+import           Data.List (inits, tails)
+import           Data.Map (Map)
+import qualified Data.Map as Map
 
 binaryToInt :: String -> Int
 binaryToInt = foldl (\a x -> a * 2 + digitToInt x) 0
@@ -28,13 +20,16 @@ right :: Either a b -> b
 right (Right b) = b
 right _ = undefined
 
-bet :: Int -> (Int, Int) -> Bool
 bet k (l, u) = k >= l && k <= u
+bet' k (l, u) = k > l && k < u
 
 -- combine filter predicates
 (&+) :: (a -> Bool) -> (a -> Bool) -> (a -> Bool)
 (&+) = liftM2 (&&)
 
+(|+) :: (a -> Bool) -> (a -> Bool) -> (a -> Bool)
+(|+) = liftM2 (||)
+
 howMany :: (a -> Bool) -> [a] -> Int
 howMany predicate = length . filter predicate
 
@@ -49,3 +44,20 @@ kadane = go 0 0
     where go :: Int -> Int -> [Int] -> Int
           go best _ [] = best
           go best current (l:ls) = go (max best (current + l)) (max current (current + l)) ls
+
+-- tuple stuff
+
+add (x, y) (a, b) = (x+a, y+b)
+shear c (x, y) = (c * x, c * y)
+inside  (p, q) (r, s) (a, b) = bet a (p, r) && bet b (q, s)
+inside' (p, q) (r, s) (a, b) = bet' a (p, r) && bet' b (q, s)
+
+-- [f, f.f, f.f.f, ...]
+repeatF f = f : map (f .) (repeatF f) 
+
+makeGrid :: String -> (Map (Int, Int) Char, Int, Int)
+makeGrid s = (grid, width, height) where
+    rows = lines s
+    grid = Map.fromList [((x, y), a) | (y, row) <- zip [0..] rows , (x, a) <- zip [0..] row]
+    width = length (head rows)
+    height = length rows