11 lines
236 B
Haskell
11 lines
236 B
Haskell
import Data.List (groupBy)
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import Data.Function (on)
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import Control.Monad (join)
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main :: IO ()
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main =
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mapM_ print $
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fmap (uncurry (*)) <$>
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groupBy
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(on (==) fst)
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(filter (uncurry (>=)) $ join ((<*>) . fmap (,)) [1 .. 12])
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