Data commit

Task/Spiral-matrix/Haskell/spiral-matrix-1.hs

@@ -0,0 +1,9 @@
+import Data.List
+import Control.Monad
+grade xs = map snd. sort $ zip xs [0..]
+values n = cycle [1,n,-1,-n]
+counts n = (n:).concatMap (ap (:) return)  $ [n-1,n-2..1]
+reshape n = unfoldr (\xs -> if null xs then Nothing else Just (splitAt n xs))
+spiral n = reshape n . grade. scanl1 (+). concat $ zipWith replicate (counts n) (values n)
+displayRow = putStrLn . intercalate " " . map show
+main = mapM displayRow $ spiral 5

Task/Spiral-matrix/Haskell/spiral-matrix-2.hs

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+import Data.List
+import Control.Applicative
+counts = tail . reverse . concat . map (replicate 2) . enumFromTo 1
+values = cycle . ((++) <$> map id <*> map negate) . (1 :) . (: [])
+grade = map snd . sort . flip zip [0..]
+copies = grade . scanl1 (+) . concat . map (uncurry replicate) . (zip <$> counts <*> values)
+parts = (<*>) take $ (.) <$> (map . take) <*> (iterate . drop) <*> copies
+disp = (>> return ()) . mapM (putStrLn . intercalate " " . map show) . parts
+main = disp 5

Task/Spiral-matrix/Haskell/spiral-matrix-3.hs

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+import Data.List (transpose)
+import Text.Printf (printf)
+
+-- spiral is the first row plus a smaller spiral rotated 90 deg
+spiral 0 _ _ = [[]]
+spiral h w s = [s .. s+w-1] : rot90 (spiral w (h-1) (s+w))
+	where rot90 = (map reverse).transpose
+
+-- this is sort of hideous, someone may want to fix it
+main = mapM_ (\row->mapM_ ((printf "%4d").toInteger) row >> putStrLn "") (spiral 10 9 1)

Task/Spiral-matrix/Haskell/spiral-matrix-4.hs

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+import Data.List (intercalate, transpose)
+
+---------------------- SPIRAL MATRIX ---------------------
+spiral :: Int -> [[Int]]
+spiral n = go n n 0
+  where
+    go rows cols x
+      | 0 < rows =
+          [x .. pred cols + x] :
+          fmap
+            reverse
+            (transpose $ go cols (pred rows) (x + cols))
+      | otherwise = [[]]
+
+
+--------------------------- TEST -------------------------
+main :: IO ()
+main = putStrLn $ wikiTable $ spiral 5
+
+
+--------------------- TABLE FORMATTING -------------------
+wikiTable :: Show a => [[a]] -> String
+wikiTable =
+  concat
+    . ("{| class=\"wikitable\" style=\"text-align: right;" :)
+    . ("width:12em;height:12em;table-layout:fixed;\"\n|-\n" :)
+    . return
+    . (<> "\n|}")
+    . intercalate "\n|-\n"
+    . fmap (('|' :) . (' ' :) . intercalate " || " . fmap show)