Added link to writeup

diff --git a/advent04/Main.hs b/advent04/Main.hs
index 0e11075009b8c0f6bada7b8af9f288a297ec1a9a..783d9f5bb8e910f22b0760c7e6603a56ad5da9f6 100644 (file)
--- a/advent04/Main.hs
+++ b/advent04/Main.hs
@@ -1,3 +1,5 @@
+-- Writeup at https://work.njae.me.uk/2021/12/04/advent-of-code-2021-day-4/
+
 import Data.Text ()
 import qualified Data.Text.IO as TIO
 
@@ -7,9 +9,12 @@ import Control.Applicative
 import Data.List
 
 type Square = [[Int]]
-type BingoSquare = [[BingoNum]]
+
 data BingoNum = BingoNum Int Bool
   deriving (Eq, Show)
+
+type BingoSquare = [[BingoNum]]
+
 data BingoState = BingoState Int [BingoSquare]
   deriving (Eq, Show)
 
@@ -52,7 +57,6 @@ pruningBingoStep (BingoState _ squares) caller = BingoState caller squares''
 hasCompletedSquare :: BingoState -> Bool
 hasCompletedSquare (BingoState _n squares) = any completed squares
 
-
 unmarkedSum :: BingoSquare -> Int
 unmarkedSum bingoSquare = 
   sum [value bn | r <- bingoSquare, bn <- r, (not $ isCalled bn)]