A quick Schwartzian Transform does the trick. Your sample is not an array of arrays BTW. I guess you are tired.

@in = (                                 
        [qw(M N)],               
        [qw(M N Q P O)],                          
        [qw(C B A)],                           
        [qw(U S)],                               
        [qw(V T)],                            
        [qw(C G F E D)],                       
        [qw(C G F H)],                         
        [qw(C G F H I)],                         
        [qw(C G F H J)],                         
        [qw(M K)],                              
);  


my @out =  map{$_->[0]}  sort{$a->[1] cmp $b->[1]}  map{[$_, concat($_
+)]} @in;

sub concat {
    my $ary = shift;
    $ary = join '', @$ary;
    $ary =~ s/\s//g;
  return $ary;
}

use Data::Dumper;
# munge the output for compactness and to make it look nicer
$Data::Dumper::Indent = 0;
print map {s/\[/\n        \[/g; $_} Dumper \@out;

__DATA__
$VAR1 = 
        [
        ['C','B','A'],
        ['C','G','F','E','D'],
        ['C','G','F','H'],
        ['C','G','F','H','I'],
        ['C','G','F','H','J'],
        ['M','K'],
        ['M','N'],
        ['M','N','Q','P','O'],
        ['U','S'],
        ['V','T']];
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.