Update HashTrees.hs

HashTrees.hs

@@ -1,11 +1,9 @@
 module HashTrees where
 
 import Data.Digest.Pure.SHA
-import Data.List
 import qualified Data.ByteString.Lazy as BL
 import Control.Monad
 import Data.List
-import Data.Bits
 
 data HashTree k a = Leaf | HashTree (Digest k) (HashTree k a) (HashTree k a) deriving (Show)
 
@@ -43,4 +41,4 @@ nextPowerOf n = 2 ^ (ceiling $ logBase 2 $ fromIntegral n)
 padHashes xs = pad' 0 xs where
     pad' n ([]) = [] ++ (take ((nextPowerOf n) - n) $ repeat BL.empty)
     pad' n (x:xs) = x : (pad' (n +1) xs)
-  
+