#!/usr/bin/perl
use strict;
use warnings;

my $a="  456 789 123 456 789  ";
my $count;
my $b=$a;
$count=$a =~ /\d+/g;
print "$count\n";

$count = () = $b =~ /\d+/g;
print "$count\n";

my @a = $b =~ /\d+/g;
$count = @a;
print "$count\n";