, isSubmapOf, isSubmapOfBy
, isProperSubmapOf, isProperSubmapOfBy
+ -- * Min\/Max
+
+ , maxView
+ , minView
+ , findMin
+ , findMax
+ , deleteMin
+ , deleteMax
+ , deleteFindMin
+ , deleteFindMax
+ , updateMin
+ , updateMax
+ , updateMinWithKey
+ , updateMaxWithKey
+ , minViewWithKey
+ , maxViewWithKey
+
-- * Debugging
, showTree
, showTreeWith
import Data.Monoid (Monoid(..))
import Data.Typeable
import Data.Foldable (Foldable(foldMap))
-
+import Control.Monad ( liftM )
{-
-- just for testing
import qualified Prelude
{--------------------------------------------------------------------
+ Min\/Max
+--------------------------------------------------------------------}
+
+-- | /O(log n)/. Update the value at the minimal key.
+updateMinWithKey :: (Key -> a -> a) -> IntMap a -> IntMap a
+updateMinWithKey f t
+ = case t of
+ Bin p m l r | m < 0 -> let t' = updateMinWithKeyUnsigned f l in Bin p m t' r
+ Bin p m l r -> let t' = updateMinWithKeyUnsigned f r in Bin p m l t'
+ Tip k y -> Tip k (f k y)
+ Nil -> error "maxView: empty map has no maximal element"
+
+updateMinWithKeyUnsigned f t
+ = case t of
+ Bin p m l r -> let t' = updateMinWithKeyUnsigned f r in Bin p m l t'
+ Tip k y -> Tip k (f k y)
+
+-- | /O(log n)/. Update the value at the maximal key.
+updateMaxWithKey :: (Key -> a -> a) -> IntMap a -> IntMap a
+updateMaxWithKey f t
+ = case t of
+ Bin p m l r | m < 0 -> let t' = updateMaxWithKeyUnsigned f r in Bin p m r t'
+ Bin p m l r -> let t' = updateMaxWithKeyUnsigned f l in Bin p m t' l
+ Tip k y -> Tip k (f k y)
+ Nil -> error "maxView: empty map has no maximal element"
+
+updateMaxWithKeyUnsigned f t
+ = case t of
+ Bin p m l r -> let t' = updateMaxWithKeyUnsigned f r in Bin p m l t'
+ Tip k y -> Tip k (f k y)
+
+
+-- | /O(log n)/. Retrieves the maximal (key,value) couple of the map, and the map stripped from that element.
+-- @fail@s (in the monad) when passed an empty map.
+maxViewWithKey :: (Monad m) => IntMap a -> m ((Key, a), IntMap a)
+maxViewWithKey t
+ = case t of
+ Bin p m l r | m < 0 -> let (result, t') = maxViewUnsigned l in return (result, bin p m t' r)
+ Bin p m l r -> let (result, t') = maxViewUnsigned r in return (result, bin p m l t')
+ Tip k y -> return ((k,y), Nil)
+ Nil -> fail "maxView: empty map has no maximal element"
+
+maxViewUnsigned t
+ = case t of
+ Bin p m l r -> let (result,t') = maxViewUnsigned r in (result,bin p m l t')
+ Tip k y -> ((k,y), Nil)
+
+-- | /O(log n)/. Retrieves the minimal (key,value) couple of the map, and the map stripped from that element.
+-- @fail@s (in the monad) when passed an empty map.
+minViewWithKey :: (Monad m) => IntMap a -> m ((Key, a), IntMap a)
+minViewWithKey t
+ = case t of
+ Bin p m l r | m < 0 -> let (result, t') = minViewUnsigned r in return (result, bin p m l t')
+ Bin p m l r -> let (result, t') = minViewUnsigned l in return (result, bin p m t' r)
+ Tip k y -> return ((k,y),Nil)
+ Nil -> fail "minView: empty map has no minimal element"
+
+minViewUnsigned t
+ = case t of
+ Bin p m l r -> let (result,t') = minViewUnsigned l in (result,bin p m t' r)
+ Tip k y -> ((k,y),Nil)
+
+
+-- | /O(log n)/. Update the value at the maximal key.
+updateMax :: (a -> a) -> IntMap a -> IntMap a
+updateMax f = updateMaxWithKey (const f)
+
+-- | /O(log n)/. Update the value at the minimal key.
+updateMin :: (a -> a) -> IntMap a -> IntMap a
+updateMin f = updateMinWithKey (const f)
+
+
+-- Duplicate the Identity monad here because base < mtl.
+newtype Identity a = Identity { runIdentity :: a }
+instance Monad Identity where
+ return a = Identity a
+ m >>= k = k (runIdentity m)
+-- Similar to the Arrow instance.
+first f (x,y) = (f x,y)
+
+
+-- | /O(log n)/. Retrieves the maximal key of the map, and the map stripped from that element.
+-- @fail@s (in the monad) when passed an empty map.
+maxView t = liftM (first snd) (maxViewWithKey t)
+
+-- | /O(log n)/. Retrieves the minimal key of the map, and the map stripped from that element.
+-- @fail@s (in the monad) when passed an empty map.
+minView t = liftM (first snd) (minViewWithKey t)
+
+-- | /O(log n)/. Delete and find the maximal element.
+deleteFindMax = runIdentity . maxView
+
+-- | /O(log n)/. Delete and find the minimal element.
+deleteFindMin = runIdentity . minView
+
+-- | /O(log n)/. The minimal key of the map.
+findMin = fst . runIdentity . minView
+
+-- | /O(log n)/. The maximal key of the map.
+findMax = fst . runIdentity . maxView
+
+-- | /O(log n)/. Delete the minimal key.
+deleteMin = snd . runIdentity . minView
+
+-- | /O(log n)/. Delete the maximal key.
+deleteMax = snd . runIdentity . maxView
+
+
+{--------------------------------------------------------------------
Submap
--------------------------------------------------------------------}
-- | /O(n+m)/. Is this a proper submap? (ie. a submap but not equal).
, split
, splitMember
+ -- * Min\/Max
+ , findMin
+ , findMax
+ , deleteMin
+ , deleteMax
+ , deleteFindMin
+ , deleteFindMax
+ , maxView
+ , minView
+
-- * Map
, map
data IntSet = Nil
| Tip {-# UNPACK #-} !Int
| Bin {-# UNPACK #-} !Prefix {-# UNPACK #-} !Mask !IntSet !IntSet
+-- Invariant: Nil is never found as a child of Bin.
+
type Prefix = Int
type Mask = Int
Tip y -> (x==y)
Nil -> False
--- | /O(log n)/. Is the element not in the set?
+-- | /O(min(n,W))/. Is the element not in the set?
notMember :: Int -> IntSet -> Bool
notMember k = not . member k
Nil -> (Nil,Nil)
--- | /O(log n)/. The expression (@'split' x set@) is a pair @(set1,set2)@
+-- | /O(min(n,W))/. The expression (@'split' x set@) is a pair @(set1,set2)@
-- where all elements in @set1@ are lower than @x@ and all elements in
-- @set2@ larger than @x@.
--
| otherwise -> (Nil,Nil)
Nil -> (Nil,Nil)
--- | /O(log n)/. Performs a 'split' but also returns whether the pivot
+-- | /O(min(n,W))/. Performs a 'split' but also returns whether the pivot
-- element was found in the original set.
splitMember :: Int -> IntSet -> (IntSet,Bool,IntSet)
splitMember x t
Nil -> (Nil,False,Nil)
{----------------------------------------------------------------------
+ Min/Max
+----------------------------------------------------------------------}
+
+-- | /O(min(n,W))/. Retrieves the maximal key of the set, and the set stripped from that element
+-- @fail@s (in the monad) when passed an empty set.
+maxView :: (Monad m) => IntSet -> m (Int, IntSet)
+maxView t
+ = case t of
+ Bin p m l r | m < 0 -> let (result,t') = maxViewUnsigned l in return (result, bin p m t' r)
+ Bin p m l r -> let (result,t') = maxViewUnsigned r in return (result, bin p m l t')
+ Tip y -> return (y,Nil)
+ Nil -> fail "maxView: empty set has no maximal element"
+
+maxViewUnsigned :: IntSet -> (Int, IntSet)
+maxViewUnsigned t
+ = case t of
+ Bin p m l r -> let (result,t') = maxViewUnsigned r in (result, bin p m l t')
+ Tip y -> (y, Nil)
+
+-- | /O(min(n,W))/. Retrieves the minimal key of the set, and the set stripped from that element
+-- @fail@s (in the monad) when passed an empty set.
+minView :: (Monad m) => IntSet -> m (Int, IntSet)
+minView t
+ = case t of
+ Bin p m l r | m < 0 -> let (result,t') = minViewUnsigned r in return (result, bin p m l t')
+ Bin p m l r -> let (result,t') = minViewUnsigned l in return (result, bin p m t' r)
+ Tip y -> return (y, Nil)
+ Nil -> fail "minView: empty set has no minimal element"
+
+minViewUnsigned :: IntSet -> (Int, IntSet)
+minViewUnsigned t
+ = case t of
+ Bin p m l r -> let (result,t') = minViewUnsigned l in (result, bin p m t' r)
+ Tip y -> (y, Nil)
+
+
+-- Duplicate the Identity monad here because base < mtl.
+newtype Identity a = Identity { runIdentity :: a }
+instance Monad Identity where
+ return a = Identity a
+ m >>= k = k (runIdentity m)
+
+
+-- | /O(min(n,W))/. Delete and find the minimal element.
+--
+-- > deleteFindMin set = (findMin set, deleteMin set)
+deleteFindMin :: IntSet -> (Int, IntSet)
+deleteFindMin = runIdentity . minView
+
+-- | /O(min(n,W))/. Delete and find the maximal element.
+--
+-- > deleteFindMax set = (findMax set, deleteMax set)
+deleteFindMax :: IntSet -> (Int, IntSet)
+deleteFindMax = runIdentity . maxView
+
+-- | /O(min(n,W))/. The minimal element of a set.
+findMin :: IntSet -> Int
+findMin = fst . runIdentity . minView
+
+-- | /O(min(n,W))/. The maximal element of a set.
+findMax :: IntSet -> Int
+findMax = fst . runIdentity . maxView
+
+-- | /O(min(n,W))/. Delete the minimal element.
+deleteMin :: IntSet -> IntSet
+deleteMin = snd . runIdentity . minView
+
+-- | /O(min(n,W))/. Delete the maximal element.
+deleteMax :: IntSet -> IntSet
+deleteMax = snd . runIdentity . maxView
+
+
+
+{----------------------------------------------------------------------
Map
----------------------------------------------------------------------}