四大机器人的代码

upring

Googlebot/2.1+(+http://www.google.com/bot.html)
Mediapartners-Google/2.1

/ I  u  I* R$ W' F8 _! M% e! mgoogle
# ?. `) B% n% s& s4 k- u0 v9 k8 H
/ r+ F9 V8 I+ c9 j6 SBaiduspider+(+http://www.baidu.com/search/spider.htm)

" W: ^- U5 P: u8 }7 K+ A0 Ubaidu

! E6 f% u) h6 l0 I+Yahoo!+Slurp;+http://help.yahoo.com/help/us/ysearch/slurp
9 s8 {; }# e9 t/ `! A( A( l4 m! oyahoo
: T1 t# v. f" X$ Z; J7 ~. l
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