1 files changed, 4 insertions, 1 deletions

diff --git a/src/Main.hs b/src/Main.hs
index 190e997..28afaa7 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -10,7 +10,10 @@ main = do
   let n = read $ head args :: Int
     in putStrLn $ intercalate "\n" $ map show $ solve n
 
-data Square = O | X | Qu deriving (Show, Eq)
+-- representation of the state of a square on the board, which can either a
+-- Queen (Q), be under attack by a Queen (X) or open/available (X)
+
+data Square = Qu | X | O deriving (Show, Eq)
 
 solve :: (Eq n, Num n) => n -> [Matrix Square]
 solve n = nub $ solveN n