use strict;
use warnings;

package Counter;

sub new {
    my ($class, $start) = @_;
    return bless {count => $start}, $class;
}

sub add {
    my ($self, $value) = @_;
    $self->{count} += $value;
}

sub get {
    my ($self) = @_;
    return $self->{count};
}


package main;

my $ctr = Counter->new (7);
print "Start: " . $ctr->get () . "\n";
$ctr->add (3);
print "End: " . $ctr->get () . "\n";