The thing which you mentioned is right one.I should skip the underscore from the rev.And should include with + inside grouping. Please look the below code.Hence i am not getting the things.Did i made any mistakes with my code.Let me know to check it? 
my $location = $output_dir;
print $location;
open LOGFILE, $location;
my $first_line = 1;
print $first_line;
my $max_id;

while (<LOGFILE>) {
    if (/rev(\d+)/) {
        if ($first_line) {
            $first_line = 0;
            print $first_line;
            $max_id = $1;
            print $max_id;
            
        } else {
            $max_id = $1 if ($1 > $max_id);
            print $max_id;
        }
    }
}

close LOGFILE;

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In reply to Re^2: How to take only maximum directory name by using its digits using perl? by finddata
in thread How to take only maximum directory name by using its digits using perl? by finddata

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