What is the regular expression for a sentence with two digit numbers?

Question

Programming

I'm trying to find a regular expression for sentences with two-digit numbers (if there are 3 or more characters in the number, it doesn't work). Tried to use

[^0-9]*[0-9][0-9][^0-9]*

but it returns true when the phrase "I have 100 rubles"
I use c#

Answer 1

/(^|\s)\d{2}?(\s|$)/

Answer 2

^[^\d]+?\d{2}[^\d]+$

Answer 3

\b\d{1,2}\b

Answer 4

uniq -u uniq.txt