Hello, I'm trying to use Data.Map to memoize computations. Unfortunately this didn't improve the runtime of f at all, so there must be something wrong with my implementation. Thanks in advance! f 1 s (HMM s0 _ sts) = s ??? sts s0 f t s hmm = memory hmm Map.! (t,s) memory hmm@(HMM s0 sss sts) = Map.fromList [ ((t,s),f' t s hmm) | t <- [1..100], s <- sss, s/=s0 ] f' 1 s (HMM s0 _ sts) = s ??? sts s0 f' t s hmm@(HMM s0 sss sts) = sum [ (memory hmm)Map.!(t-1,s') * (s ??? sts s') | s' <- sss, s' /= s0 ] _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/