From e76f6672781bd1a4d50a0fc9451f474bc81176cb Mon Sep 17 00:00:00 2001 From: Andrew Cady Date: Fri, 14 Jun 2019 10:16:00 -0400 Subject: minor style changes --- src/MyQueens.hs | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/MyQueens.hs b/src/MyQueens.hs index bc7da02..a3c5e0b 100644 --- a/src/MyQueens.hs +++ b/src/MyQueens.hs @@ -21,7 +21,7 @@ allOptionsBoard = take 8 $ repeat allOptionsColumn select :: Board -> [Board] select (x@(RankChoice _):xs) = map (x:) (select xs) -select ((RankOptions rs):xs) = dropHopeless $ map (\r -> (RankChoice r):(restrict xs r)) rs +select ((RankOptions rs):xs) = dropHopeless $ map (restrict xs) rs select [] = error "select on invalid board" dropHopeless :: [Board] -> [Board] @@ -36,7 +36,7 @@ filterRankOptions f (RankOptions rs) = RankOptions (filter f rs) filterRankOptions _ x = x restrict :: PartialBoard -> Rank -> PartialBoard -restrict rs r = +restrict rs r = ((RankChoice r) :) $ (dropDiagonal pred minBound r) . (dropDiagonal succ maxBound r) . (map (filterRankOptions (/= r))) $ @@ -51,7 +51,7 @@ select' :: [Board] -> [Board] select' = concatMap select queens :: [Board] -queens = select' . select' . select' . select' . select' . select' . select' . select' $ [allOptionsBoard] +queens = foldl1 (.) (take 8 $ repeat select') $ [allOptionsBoard] main :: IO () main = do -- cgit v1.2.3