use strict;
use warnings;

use List::MoreUtils 'uniq';
use MCE::Map;

sub GenUniStrings {
    # https://www.perlmonks.org/?node_id=11121889
    my ($numOnes, $strLen) = @_;
    my @strings;

    die "Number of ones can't be zero or negative" if $numOnes < 1;

    for my $prefixSize (0 .. $strLen - $numOnes) {
        my $prefix = '0' x $prefixSize;
        my $tailLen = $strLen - $prefixSize - 1;

        if ($numOnes == 1) {
            push @strings, $prefix . '1' . ('0' x $tailLen);
        } else {
            push @strings, map {$prefix . '1' . $_}
                GenUniStrings($numOnes - 1, $tailLen);
        }
    }

    return @strings;
}

my ($numOnes, $strLen) = (9, 25);

my @input_data = uniq map { substr $_, 0, $numOnes - 1 }
    GenUniStrings($numOnes - 1, $numOnes * 2 - 2);

# print "$_\n" for @input_data;
# exit;

MCE::Map::init {
    max_workers => MCE::Util::get_ncpu() >> 1,
    chunk_size => 1,
};

my @strings = mce_map {
    my $count = $numOnes - tr/1//;
    my $head = $_;
    map { $head . $_ } GenUniStrings($count, $strLen - length($head));
} @input_data;

print "$_\n" for @strings;