tasks a-s

Task/Non-continuous-subsequences/Haskell/non-continuous-subsequences-3.hs

@@ -0,0 +1,10 @@
+import Data.List
+
+poset = foldr (\x p -> p ++ map (x:) p) [[]]
+
+ncsubs [] = [[]]
+ncsubs (x:xs) = tail $ nc [x] xs
+  where
+    nc [_] [] = [[]]
+    nc (_:x:xs) [] = nc [x] xs
+    nc  xs (y:ys) = (nc (xs++[y]) ys) ++ map (xs++) (tail $ poset ys)