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style: lint

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This commit is contained in:
Mahdi Dibaiee 2016-03-18 17:51:36 +03:30
parent 69c54f4e56
commit d83dcba48d
1 changed files with 9 additions and 9 deletions
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18
index.hs
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@ -36,8 +36,8 @@ module Huffman ( tree, charSequence, decode )
charSequence node ch =
fromJust $ helper node ch ""
where
helper (Node { symbol = s, left = l, right = r }) ch sequ
| (isJust s) && (fromJust s == ch) = Just sequ
helper Node { symbol = s, left = l, right = r } ch sequ
| s == Just ch = Just sequ
| isNothing l && isNothing r = Nothing
| otherwise = let leftPath = helper (fromJust l) ch (sequ ++ "0")
rightPath = helper (fromJust r) ch (sequ ++ "1")
@ -45,8 +45,8 @@ module Huffman ( tree, charSequence, decode )
-- Root-to-leaf search, find a character based on sequence string
findChar :: Node -> String -> Maybe Char
findChar n@(Node { symbol = s, left = l, right = r}) sequ
| length sequ > 0 = let path = if head sequ == '0' then l else r
findChar n@Node { symbol = s, left = l, right = r} sequ
| not $ null sequ = let path = if head sequ == '0' then l else r
in if isJust path then
findChar (fromJust path) (tail sequ)
else
@ -59,7 +59,7 @@ module Huffman ( tree, charSequence, decode )
encode :: String -> String
encode input = let t = tree input
table = charTable t input
in concat $ map (\a -> fromJust $ Map.lookup a table) input
in concatMap (\a -> fromJust $ Map.lookup a table) input
-- Character table, a Map representing each character's bit sequence
charTable :: Node -> String -> Map.Map Char String
@ -72,10 +72,10 @@ module Huffman ( tree, charSequence, decode )
-- Decode a string, given the tree representing it
decode :: Node -> String -> String
decode t input = let (valid, next) = span (isNothing . findChar t) $ inits input
sequ = (head next)
ninput = (tails input) !! (length valid)
sequ = head next
ninput = tails input !! length valid
ch = fromJust $ findChar t sequ
in if length ninput > 0 then
ch:(decode t ninput)
in if not $ null ninput then
ch : decode t ninput
else
[ch]