Just to give you the fishing rod, you can peruse perlre for all you want to know about regexes in Perl. And here's a free fish about quantifiers:

       The following standard quantifiers are recognized:
 
           *      Match 0 or more times
           +      Match 1 or more times
           ?      Match 1 or 0 times
           {n}    Match exactly n times
           {n,}   Match at least n times
           {n,m}  Match at least n but not more than m times

Note that n can be 0 in the last one. Enjoy your meal :)