Hofstadter Figure-Figure sequences: Difference between revisions

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@@ Line 980: / Line 980: @@
 <lang haskell>import Data.List (sort)
+r :: [Int]
 r = scanl (+) 1 s
-s = 2:4:tail (compliment (tail r)) where
-	compliment = concat.interval
-	interval x = zipWith (\x y -> [x+1..y-1]) x (tail x)
+s :: [Int]
+s = 2 : 4 : tail (complement (tail r))
+  where
+    complement = concat . interval
+    interval x = zipWith (\x y -> [succ x .. pred y]) x (tail x)
+main :: IO ()
 main = do
-	putStr "R: "; print (take 10 r)
+  putStr "R: "
-	putStr "S: "; print (take 10 s)
+  print (take 10 r)
-	putStr "test 1000: ";
+  putStr "S: "
+  print (take 10 s)
-	print ([1..1000] == sort ((take 40 r) ++ (take 960 s)))</lang>
+  putStr "test 1000: "
+  print $ [1 .. 1000] == sort (take 40 r ++ take 960 s)</lang>
 output:
 <pre>