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Added haskell version.
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YOUHAVEPUTON7.5POUNDSSINCEISAWYOU.
</pre>
=={{header|Haskell}}==
<lang haskell>import Data.Char
import Data.Map
charToInt :: Char -> Int
charToInt c = ord c - ord '0'
-- Given a string, decode a single character from the string.
-- Return the decoded char and the remaining undecoded string.
decodeChar :: String -> (Char,String)
decodeChar ('7':'9':r:rs) = (r,rs)
decodeChar ('7':r:rs) = ("PQUVWXYZ. " !! charToInt r, rs)
decodeChar ('3':r:rs) = ("ABCDFGIJKN" !! charToInt r, rs)
decodeChar (r:rs) = ("HOL MES RT" !! charToInt r, rs)
-- Decode an entire string.
decode :: String -> String
decode [] = []
decode st = let (c, s) = decodeChar st in c:decode s
-- Given a string, decode a single character from the string.
-- Return the decoded char and the part of the encoded string
-- used to encode that character.
revEnc :: String -> (Char, String)
revEnc enc = let (dec, rm) = decodeChar enc in (dec, take (length enc - length rm) enc)
ds :: String
ds = ['0'..'9']
-- Decode all 1000 possible encodings of three digits and
-- use results to construct map used to encode.
encodeMap :: Map Char String
encodeMap = fromList [ revEnc [d2,d1,d0] | d2 <- ds, d1 <- ds, d0 <- ds ]
-- Encode a single char using encoding map.
encodeChar :: Char -> String
encodeChar c = findWithDefault "" c encodeMap
-- Encode an entire string.
encode :: String -> String
encode st = concatMap encodeChar $ fmap toUpper st
-- Test by encoding, decoding, printing results.
main = let orig = "One night-it was on the twentieth of March, 1888-I was returning"
enc = encode orig
dec = decode enc
in mapM_ putStrLn [ "Original: " ++ orig
, "Encoded: " ++ enc
, "Decoded: " ++ dec ]</lang>
{{out}}
<pre style="font-size:80%">Original: One night-it was on the twentieth of March, 1888-I was returning
Encoded: 139539363509369743061399059745399365901344308320791798798798367430685972839363935
Decoded: ONENIGHTITWASONTHETWENTIETHOFMARCH1888IWASRETURNING
</pre>
=={{header|Icon}} and {{header|Unicon}}==
<lang Icon>procedure main()
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