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Groups > comp.lang.c++ > #82507

Re: binary_search accoring to its name

From Juha Nieminen <nospam@thanks.invalid>
Newsgroups comp.lang.c++
Subject Re: binary_search accoring to its name
Date 2021-11-29 05:57 +0000
Organization Aioe.org NNTP Server
Message-ID <so1q3b$1at4$1@gioia.aioe.org> (permalink)
References <sntftt$o7$1@dont-email.me> <snvp3h$14tmm$1@gwaiyur.mb-net.net>

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Marcel Mueller <news.5.maazl@spamgourmet.org> wrote:
> Assuming than a three way comparison is often a bit more expensive, it 
> might even be less efficient for some collections.

And not only does it require a slower three-way comparison, it also uses two
conditionals instead of the one that std::binary_search/std::lower_bound
uses. Depending on the situation the additional conditional may actually
make the code slightly slower (especially since it's likely that the CPU
won't predict it correctly in about half the iterations, on average).
Unpredictable conditionals are performance killers.

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Thread

binary_search accoring to its name Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-27 15:38 +0100
  Re: binary_search accoring to its name Marcel Mueller <news.5.maazl@spamgourmet.org> - 2021-11-28 12:27 +0100
    Re: binary_search accoring to its name Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-28 17:03 +0100
    Re: binary_search accoring to its name Juha Nieminen <nospam@thanks.invalid> - 2021-11-29 05:57 +0000
      Re: binary_search accoring to its name Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-29 08:26 +0100
        Re: binary_search accoring to its name Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-29 14:02 +0100

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