1st commit on 070_haskell

3 files changed, 40 insertions, 1 deletions

diff --git a/challenge-070/stuart-little/README b/challenge-070/stuart-little/README
index 76119cbbb8..78439907de 100644
--- a/challenge-070/stuart-little/README
+++ b/challenge-070/stuart-little/README
@@ -1 +1 @@
-Solutions by Stuart Little.
+Solutions by Stuart Little
diff --git a/challenge-070/stuart-little/haskell/ch-1.hs b/challenge-070/stuart-little/haskell/ch-1.hs
new file mode 100755
index 0000000000..1c02f0accd
--- /dev/null
+++ b/challenge-070/stuart-little/haskell/ch-1.hs
@@ -0,0 +1,20 @@
+#!/usr/bin/env runghc
+
+-- run <script> <string> <count> <offset>
+
+import Data.List.Split (splitPlaces,)
+import System.Environment (getArgs,)
+
+swapChunks :: Int -> Int -> [a] -> [a]
+swapChunks count offset xs
+  |count+offset < ln = l0 ++ l3 ++ l2 ++ l1 ++ l4
+  |count+offset == ln = m2 ++ m4 ++ m0 ++ m3 ++ m1
+  where
+    ln = length xs
+    (l0:l1:l2:l3:l4:_) = splitPlaces [1,count,offset-count,count,ln-offset-count-1] xs
+    (m0:m1:m2:m3:m4:_) = splitPlaces [1,count-1,1,offset-count,count-1] xs
+
+main = do
+  (str:rest) <- getArgs
+  let (count:offset:_) = map (read::String->Int) rest
+  putStrLn $ swapChunks count offset str
diff --git a/challenge-070/stuart-little/haskell/ch-2.hs b/challenge-070/stuart-little/haskell/ch-2.hs
new file mode 100755
index 0000000000..6be8c6a6f0
--- /dev/null
+++ b/challenge-070/stuart-little/haskell/ch-2.hs
@@ -0,0 +1,19 @@
+#!/usr/bin/env runghc
+
+-- run <script> <nr of bits>
+
+import Data.List.Split (chunksOf,)
+import System.Environment (getArgs,)
+
+binStrToDec :: String -> Int
+binStrToDec b = sum $ zipWith (*) (iterate (2*) 1) $ map (read::String->Int) $ chunksOf 1 $ reverse b
+
+gray :: Int -> [String]
+gray n
+  |n==0 =[""]
+  |otherwise = (map ('0':) l) ++ (map ('1':) $ reverse l) where
+     l = gray (n-1)
+
+main = do
+  nrbits <- getArgs >>= return.(read::String->Int).head
+  print $ map binStrToDec $ gray nrbits