12 lines
371 B
Haskell
12 lines
371 B
Haskell
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import Data.List
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group' :: [Int] -> [a] -> [[[a]]]
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group' ln ls = map ((([([fst] <*>)] <*>) . groupBy grouper . sortBy sorter) . zip ls) (nub (permutations placers))
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where
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placers = concatMap (uncurry replicate) (zip ln [0 ..])
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sorter (_, r1) (_, r2) = r1 `compare` r2
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grouper (_, r1) (_, r2) = r1 == r2
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group3 :: [a] -> [[[a]]]
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group3 = group' [2, 3, 4]
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