11 lines
244 B
Haskell
11 lines
244 B
Haskell
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import Data.List
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poset = foldr (\x p -> p ++ map (x:) p) [[]]
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ncsubs [] = [[]]
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ncsubs (x:xs) = tail $ nc [x] xs
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where
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nc [_] [] = [[]]
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nc (_:x:xs) [] = nc [x] xs
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nc xs (y:ys) = (nc (xs++[y]) ys) ++ map (xs++) (tail $ poset ys)
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