++--------+-------++--------+---- one or more digits || | || | VV V VV V 1/LC-13/E10GbE-1,01/LC-14/E10GbE-1 A A A A | | | | +---------+-------+---------+---- if preceded by hyphen/dash ++--------+---- one or more digits || | VV V 1/LC-13/E10GbE-1 A A | | +---------+---- if preceded by hyphen/dash #### Win8 Strawberry 5.8.9.5 (32) Thu 10/14/2021 17:41:51 C:\@Work\Perl\monks >perl -Mstrict -Mwarnings for my $str ( '01/LC-13/E10GbE-1,01/LC-14/E10GbE-1', '01/LC-13/E10GbE-1', ) { my @m = $str =~ m{ (?<= -) \d+ }xmsg; print "'$str' ->"; print " '$_'" for @m; print "\n"; } ^Z '01/LC-13/E10GbE-1,01/LC-14/E10GbE-1' -> '13' '1' '14' '1' '01/LC-13/E10GbE-1' -> '13' '1'