工具类，boost,hah ha kla a a ga gfeaq rfd a ag ad g fggtqre -Tools for boost,very useful,hope it is help aa aa hgsfhg fag ag sg gsfg af aewr h j k h ld a r a f fa ga r a a hgah a gf gf ag dfsg afg aghfh rww s a a a a hggs