13 lines
251 B
Haskell
13 lines
251 B
Haskell
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comb :: Int -> [a] -> [[a]]
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comb m xs = combsBySize xs !! m
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where
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combsBySize = foldr f ([[]] : repeat [])
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f x next =
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zipWith
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(<>)
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(fmap (x :) <$> ([] : next))
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next
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main :: IO ()
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main = print $ comb 3 [0 .. 4]
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