haskell - Why does this code run slower on spoj, triggering the timeout? -

i trying solve problem on spoj: http://www.spoj.com/problems/palin/

my code works fine , fast on laptop (even slower cpu 1 spoj provides) spoj keeps giving me time exceeded:

import control.monad  main =         num <- getline         inputs <- replicatem (read num) getline         test inputs  test [] = return () test (l:ls) =     putstrln (send l)     test ls  send :: string -> string send str     | odd (length str) = makepalindrome str (take (length str `div` 2 + 1) str ++ ( reverse $ take (length str `div` 2) str))     | otherwise        = makepalindrome str (take (length str `div` 2) str ++ (reverse $ take (length str `div` 2) str)) makepalindrome :: string -> string  -> string makepalindrome str pal          | (read str :: integer) < (read pal :: integer) = pal         | otherwise = makepalindrome str (nextpalindrome pal)   nextpalindrome :: string -> string nextpalindrome (x:xs) = succ' ++ (reverse $ take rightlen succ')                     strlen = length (x:xs)             allnine = ( (==) '9')              odd' = odd strlen             left = if odd' take (strlen `div` 2 + 1) (x:xs)  else take (strlen `div` 2) (x:xs)             rightlen = strlen - (length left)             succ' = show (read left + 1)   checkpalindrome :: string -> bool checkpalindrome str = str == (reverse str)