#!/usr/bin/env perl -l

use strict;
use warnings;

my @dd = qw/AA JJ CC M 1 1 3 4 D JJ 1 1 D M 3 3 4 D C M 3 3 3 D P Z/;

my $in_group = 0;
my (@group, @all_groups);

for (@dd) {
    $in_group = 1 if $_ eq 'M';

    next unless $in_group;

    push @group, $_;

    if ($_ eq 'D') {
        push @all_groups, [ @group ];
        @group = ();
        $in_group = 0;
    }
}

print "@$_" for @all_groups;

##</code><code>##

M 1 1 3 4 D
M 3 3 4 D
M 3 3 3 D