February 2017
Intermediate to advanced
368 pages
8h 21m
Japanese
Content preview from Optimized C++ ―最適化、高速化のためのプログラミングテクニック
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
250
11 章 I/O を最適化する
たが、
1,972
ミリ秒（
VS2010
）と
2,110
ミリ秒（
VS2015
）かかった。
stream_write_line()
は
std::endl
のついた各行を出力する。
endl
について私が知らなかった
のは、それが出力をフラッシュすることだ。
std::endl
がなければ、書き込みはより速くなったは
ずだ。
std::ofstream
は
OS
にデータの大きなブロックを書き出すだけだからだ。例
11-15
はこの
仮説をテストする。
例
11-15
stream_write_line_noflush
()
の方が速い
void stream_write_line_noflush(std::ostream& f,
std::string const& line) {
f << line << "\n";
}
もちろん、
stream_write_line_noflush()
は、
f.flush()
で終わるか、ストリームを閉じるかし
て、最後のバッファにあるデータを書き出さねばならない。
stream_write_line_noflush()
はファ
イルを
367
ミリ秒（
VS2010
）と
302
ミリ秒（
VS2015
）で、
stream_write_line()
よりほぼ
5
倍速
くファイルを書いた。
私はファイル全体を
1
つの文字列で書く
stream_write_line_noflush()
呼び出しも試した。期
待通り、これはもっと速く、テストループが
132
ミリ秒（
VS2010
）と
137
ミリ秒（
VS2015 ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.