如何使用正则表达式查找不属于日期的两位数

How to find two digit number that is not part of a date using regular expression

我有这么长的字符串值:

"10 12 10/05/2014 p4=34"

我只想得到两位数字(带下划线):

"10 12 10/05/2014 p4=34"
 -- --               -- 

所以结果应该是

10 12 34

尝试一下:

(?<![\d/])\d\d(?![\d/])

其中:

(?<![\d/])  : negative lookbehind, assumes there're no digits nor slashes before.
\d\d        : 2 digits.
(?![\d/])   : negative lookahead, assumes there're no digits nor slashes after.