use v5.32;
use MCE::Child;
use Data::Dumper;

our @results;

MCE::Child->init(
    max_workers => 8,
    posix_exit  => 1,
    on_finish   => sub {
        my ($pid, $exit_code, $ident, $exit_signal, $core_dump, $data_ref) = @_;
        push @results, ${$data_ref};
    }
);

our @duplicated = (10..20);
our $ctr = 0;

say "processing duplicates...";
foreach my $pid (@duplicated) {
    unless ($ctr % 1000) {say $ctr;}
    $ctr++;
    MCE::Child->create(sub {
        #do stuff
        my $ans = $pid;
        return \$ans;
    });
}

MCE::Child->wait_all;

say scalar(@results);
# print Dumper(\@results);