Huffman coding: Difference between revisions
→{{header|Haskell}}: Specified imports, provided a `main`, some <$> -> fmap for simpler bracketing
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=={{header|Haskell}}==
Credits go to [http://www.haskell.org/haskellwiki/99_questions/46_to_50#Problem_50 huffman] where you'll also find a non-tree solution. Uses sorted list as a priority queue.
<lang haskell>import Data.List (group, insertBy, sort, sortBy)
import Control.Arrow ((&&&), second)
import Data.Ord (comparing)
data HTree a
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test :: String -> IO ()
test =
mapM_ (\(a, b) -> putStrLn ('\'' : a : ("
serialize . huffmanTree . freq
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huffmanTree =
snd .
head . until (null . tail) hstep . sortBy (comparing fst) . fmap (second Leaf
hstep
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:: Ord a
=> [a] -> [(Int, a)]
freq =
main :: IO ()
main = test "this is an example for huffman encoding"</lang>
{{out}}
<lang haskell>
'r' : 00001
'g' : 00010
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