Added some algorithms in Haskell

Array/kadane.hs

@@ -0,0 +1,24 @@
+-- kadane.hs
+-- Kadane's algorithm in Haskell
+
+module Main where
+
+-- returns the maximum sum of the substring
+kadane :: [Int] -> Int
+kadane = snd . foldl step (0, minBound)
+  where
+    step (currentMax, globalMax) x =
+        let newCurrent = max x (currentMax + x)
+            newGlobal  = max globalMax newCurrent
+        in (newCurrent, newGlobal)
+
+-- Example usage
+main :: IO ()
+main = do
+    let arr = [−2,1,−3,4,−1,2,1,−5,4]
+    putStrLn "Array:"
+    print arr
+
+    let maxSum = kadane arr
+    putStrLn "\nMaximum subarray sum:"
+    print maxSum

Bits Manipulation/bitReverse.hs

@@ -0,0 +1,31 @@
+-- bitReverseDemo.hs
+-- Demonstracja bitReverse64 w Haskellu
+
+module Main where
+
+import Data.Bits
+import Data.Word
+import Numeric (showHex)
+
+-- | Bit-reverse for 64-bit words.
+bitReverse64 :: Word64 -> Word64
+bitReverse64 x0 =
+  let x1 = ((x0 `shiftR` 1) .&. 0x5555555555555555) .|. ((x0 .&. 0x5555555555555555) `shiftL` 1)
+      x2 = ((x1 `shiftR` 2) .&. 0x3333333333333333) .|. ((x1 .&. 0x3333333333333333) `shiftL` 2)
+      x3 = ((x2 `shiftR` 4) .&. 0x0F0F0F0F0F0F0F0F) .|. ((x2 .&. 0x0F0F0F0F0F0F0F0F) `shiftL` 4)
+      x4 = ((x3 `shiftR` 8) .&. 0x00FF00FF00FF00FF) .|. ((x3 .&. 0x00FF00FF00FF00FF) `shiftL` 8)
+      x5 = ((x4 `shiftR` 16) .&. 0x0000FFFF0000FFFF) .|. ((x4 .&. 0x0000FFFF0000FFFF) `shiftL` 16)
+      x6 = (x5 `shiftR` 32) .|. (x5 `shiftL` 32)
+  in x6
+
+-- Helper to display Word64 in hex
+showW64Hex :: Word64 -> String
+showW64Hex w = "0x" ++ showHex w ""
+
+-- Example usage
+main :: IO ()
+main = do
+    let x = 0x0123456789ABCDEF
+    putStrLn $ "Original:  " ++ showW64Hex x
+    let rev = bitReverse64 x
+    putStrLn $ "Bit-reversed: " ++ showW64Hex rev