package Counter;

use strict;
use threads;
use threads::shared;

sub new {
    my $proto = shift;
    my $class = ref($proto) || $proto;
    my $self = {};

    my $counter :shared = shift; ## Local shared variable

    $self->{ counter } = \$counter; ## Store a reference to it in the object

    bless($self,$class);
    return $self;
}

sub incCounter {
    my $self = shift;
    lock ${ $self->{ counter } };
    ++${ $self->{ counter } };
}

sub getCounter {
    my $self = shift;
    lock ${ $self->{ counter } };
    ${ $self->{ counter } };
}
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