TimeOut on CodeChef

Question

I am new to CodeChef and am thinking of trying to solve a few problems, so I solved the "Gold coins in Bytelandian" problem. ( http://www.codechef.com/problems/COINS/ ) I get instant results on my computer, CodeChef sets a 9-second deadline, but I still get TimeOuts from CodeChef. I no longer have any clues what causes this. Any hints would be helpful.

My code is:

module Main where import qualified Data.Map as M import Data.Map (Map) import Data.Maybe main = do catch (main' M.empty 1) (const $ return ()) main' _ 11 = return () main' mc = do x <- readLn let (k,m2) = sol mx print k main' m2 (c+1) sol :: Map Integer Integer -> Integer -> (Integer, Map Integer Integer) sol mx |M.member xm = (fromJust $ M.lookup xm,m) |x > x2+x3+x4 = (x,M.insert xxm) |otherwise = (fullSoll, M.insert x fullSoll m4) where x2 = div x 2 x3 = div x 3 x4 = div x 4 (sx2, m2) = sol m x2 (sx3, m3) = sol m2 x3 (sx4, m4) = sol m3 x4 fullSoll = sx2+sx3+sx4 

Answer 1

Your sol does not end when x == 0 . When x is 1, this is normal because all x2, x3, x4 are 0, and their sum is less than x , which means that the second defender is true and not recursive. However, when the input signal is 0, the recursive case is triggered and it never ends.