From: Goswin von Brederlow <goswin-v-b@web.de>
To: Diego Olivier Fernandez Pons <dofp.ocaml@gmail.com>
Cc: Gabriel Scherer <gabriel.scherer@gmail.com>,
caml-list <caml-list@inria.fr>
Subject: Re: [Caml-list] print_int is too slow
Date: Mon, 25 Jun 2012 12:07:17 +0200 [thread overview]
Message-ID: <87lijb1z8q.fsf@frosties.localnet> (raw)
In-Reply-To: <CAHqiZ-KRTmTC4196dikqj8B5t4F84xEJTONaX4+Ns2UhjgeJtQ@mail.gmail.com> (Diego Olivier Fernandez Pons's message of "Sun, 24 Jun 2012 21:08:04 +0200")
Diego Olivier Fernandez Pons <dofp.ocaml@gmail.com> writes:
> Gabriel,
>
>> I have no time for empirical checks right now, but is the problem
>> really with print_int, or does replacing (print_newline ()) by
>> (print_string "\n") similarly improves performances? That may very
>> well be related to when buffering happens.
>
> You are right, it's print_newline() that is causing the problem
>
> (> 2s) print_int !length; print_newline ()
> (0.27s) printf.printf "%i\n" !length
> (0.21s) print_int !length; print_string "\n"
>
> I know that is not much of a difference... but it's the IOI training
> exercises and time limits are hard.
> Besides on this case that difference was larger than what I could gain
> with smarter algorithms or better data structure (I tried a dozen
> variants)
>
> Diego Olivier
What about printf.printf "%i\n%!" !length? Is that just as slow as
print_newline ()? If so then it truely is just the flushing of buffers.
MfG
Goswin
prev parent reply other threads:[~2012-06-25 10:07 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-24 18:40 Diego Olivier Fernandez Pons
2012-06-24 18:59 ` Gabriel Scherer
2012-06-24 19:08 ` Diego Olivier Fernandez Pons
2012-06-24 19:18 ` Oliver Bandel
2012-06-24 19:26 ` Diego Olivier Fernandez Pons
2012-06-24 19:48 ` Adrien
[not found] ` <20120624.220220.2022399462583597382.Christophe.Troestler@umons.ac.be>
2012-06-24 22:19 ` Diego Olivier Fernandez Pons
2012-06-24 23:06 ` Lukasz Stafiniak
2012-06-24 23:52 ` Anthony Tavener
2012-06-25 0:09 ` Diego Olivier Fernandez Pons
2012-06-25 11:39 ` oliver
2012-06-25 13:04 ` Gabriel Scherer
2012-06-25 14:25 ` oliver
2012-06-25 17:31 ` Florian Weimer
2012-06-25 10:07 ` Goswin von Brederlow [this message]
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