How do I access captured substrings after a successful regex match in Perl?

Question

I am searching for a string in Perl and storing it in another scalar variable. I want to print this scalar variable. The code below doesn\'t seem to work. I am not sure what is

Answer 1

m// returns the captured matches in list context:

#!/usr/bin/perl

use strict;
use warnings;

my $pattern = qr/^\s{10}([0-9]{2})\s[A-Z]/;

while ( my $line =  ) {
    if ( my ($n) = $line =~ $pattern ) {
        print "$n\n";
    }
}

__DATA__
          13 E 0.496 -> Q 0.724
          18 S 0.507 -> R 0.513
          19 N 0.485 -> S 0.681
          21 N 0.557 -> K 0.482