Data commit

Task/Determine-if-a-string-has-all-the-same-characters/Haskell/determine-if-a-string-has-all-the-same-characters-1.hs

@@ -0,0 +1,32 @@
+import Numeric (showHex)
+import Data.List (span)
+import Data.Char (ord)
+
+inconsistentChar :: Eq a => [a] -> Maybe (Int, a)
+inconsistentChar [] = Nothing
+inconsistentChar xs@(x:_) =
+  let (pre, post) = span (x ==) xs
+  in if null post
+       then Nothing
+       else Just (length pre, head post)
+
+
+---------------------------TEST----------------------------
+samples :: [String]
+samples = ["   ", "2", "333", ".55", "tttTTT", "4444 444"]
+
+main :: IO ()
+main = do
+  let w = succ . maximum $ length <$> samples
+      justifyRight n c = (drop . length) <*> (replicate n c ++)
+      f = (++ "' -> ") . justifyRight w ' ' . ('\'' :)
+  (putStrLn . unlines) $
+    (\s ->
+        maybe
+          (f s ++ "consistent")
+          (\(n, c) ->
+              f s ++
+              "inconsistent '" ++
+              c : "' (0x" ++ showHex (ord c) ")" ++ " at char " ++ show (succ n))
+          (inconsistentChar s)) <$>
+    samples

Task/Determine-if-a-string-has-all-the-same-characters/Haskell/determine-if-a-string-has-all-the-same-characters-2.hs

@@ -0,0 +1,5 @@
+import Data.List (findIndex)
+
+inconsistentChar :: Eq a => [a] -> Maybe (Int, a)
+inconsistentChar [] = Nothing
+inconsistentChar xs@(x:_) = findIndex (x /=) xs >>= Just . ((,) <*> (xs !!))