#!/usr/bin/perl
use strict;
use warnings;
use MCE;
use MCE::Candy;

my $volume      = 26*26;
my $max_workers = 4;
my $chunk_size  = int $volume / $max_workers;
my @results;

my $mce = MCE->new(
   max_workers => $max_workers,
   chunk_size  => $chunk_size,
   gather => MCE::Candy::out_iter_array(\@results),
   user_func => sub {
      my ($mce, $chunk_ref, $chunk_id) = @_;
      my @output;
      foreach my $item (@{ $chunk_ref }) {
         push @output, $item++;
      }
      $mce->gather($chunk_id, @output);
   }
);

$mce->process([ 'aa' .. 'zz' ]);

print "$_, " for @results;
print scalar @results, "\n";