In addition to the problem of the extraneous underscore in  /rev_(\d)+/ in the OP, note also that  (\d)+ will not match what I think you think it will if there is more than one digit present: 

c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = 'foorev_123bar';
 ;;
 print qq{captured '$1'} if $s =~ m{ rev_ (\d)+ }xms;
"
captured '3'

[download]
Capture multiple digits with: 
c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = 'foorev_123bar';
 ;;
 print qq{captured '$1'} if $s =~ m{ rev_ (\d+) }xms;
"
captured '123'

[download]
One previous reply has implicitly noted this problem. (Update: haukex has also addressed this below.)

Give a man a fish:  <%-{-{-{-<

In reply to Re: How to take only maximum directory name by using its digits using perl? by AnomalousMonk
in thread How to take only maximum directory name by using its digits using perl? by finddata

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