use strict;
use warnings;
use MCE::Child;
use MCE::Channel;
use Time::HiRes 'time';

my $workQueue = MCE::Channel->new(impl => 'Mutex');
my $numWorkers = 4;

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

MCE::Child->create(sub{DoWork($workQueue)}) for 1..$numWorkers;

$workQueue->enqueue($_) for @tokens;
$workQueue->end();

my %result = map { %{ $_->join() } } MCE::Child->list;

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900

exit;

sub DoWork {
    my ($workQueue) = @_;
    my %result; # store locally
    while (my $token = $workQueue->dequeue()) {
        my $regex = build_regex($token);
        my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
        $result{$token} = \@line_results if @line_results;
    }
    return \%result;
}