]> Hi Michal, [...] > Key points of my implementation: [...] > 3. It doesn't use Scanf. For such linear task as this Scanf takes 10 or > more times to parse input then actual computations. [...] > -- > : Michal Moskal :: http://www.kernel.pl/~malekith : GCS {C,UL}++++$ a? !tv > : When in doubt, use brute force. -- Ken Thompson : {E-,w}-- {b++,e}>+++ h I'm sorry to report that I was so puzzled by your number 3) key point, that I tested your code and a ``purely scanf'' version to see this ``10 or more times to parse'' behaviour; I didn't notice any runtime difference between the two (native code compiled) versions. Am I missing something ? Could you please try to use the following version of your read function, and report the runtime difference between your hand written code ? (BTW, I compiled the 2 programs using ocamlopt -unsafe -inline 9) let read () = try Scanf.bscanf Scanf.Scanning.stdib " %c" (function | 'D' -> Scanf.bscanf Scanf.Scanning.stdib " %d %d %s" (fun x y s -> D (x, y, s)) | 'F' -> Scanf.bscanf Scanf.Scanning.stdib " %d %s" (fun x s -> F (x, s)) | _ -> invalid_arg "read") with End_of_file -> Eof You should also replace (* let l = read_line () in let (dh, fh) = Scanf.sscanf l "R 0 %[^\n]" start in *) by let (dh, fh) = Scanf.bscanf Scanf.Scanning.stdib "R 0 %s@\n" start in Looking forward for reading from you, Pierre Weis INRIA, Projet Cristal, Pierre.Weis@inria.fr, http://pauillac.inria.fr/~weis/ ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners