Hi, i have compared a C++ implementation with a Haskell implementation of the Monte Carlo Pi approximation: http://lennart.kudling.de/haskellPi/ The Haskell version is 100 times slower and i wonder whether i do something obvious wrong. Profiling says that the majority of the time is spend in "main". But i have no idea where. Can someone give me a hint? Thanks, Lenny individual inherited COST CENTRE MODULE no. entries %time %alloc %time %alloc MAIN MAIN 1 0 0.0 0.0 100.0 100.0 main Main 254 1 88.1 90.8 100.0 100.0 monteCarloPi Main 255 1 0.6 1.1 11.9 9.2 pairs Main 257 10000000 0.7 1.4 0.7 1.4 countHits Main 256 10000001 4.2 2.9 10.6 6.7 accumulateHit Main 258 27852236 3.0 2.3 6.4 3.8 isInCircle Main 259 30000000 3.3 1.5 3.3 1.5 CAF:lit_r1A7 Main 248 1 0.0 0.0 0.0 0.0 isInCircle Main 260 0 0.0 0.0 0.0 0.0