%foo =(
'11' =>{
       '4'=>'Four',
	   },
'33' =>{
       '1'=>'One',
	   },
'2' =>{
      '2' => 'Two',
      }, 

);


   my $ref_HoH = \%foo;

    for my $k ( sort {%{ $ref_HoH{$a} } <=> %{ $ref_HoH{$b} }    }keys %$ref_HoH ) {
        print "$k\n";

        for my $j ( sort keys %{$ref_HoH->{ $k }} ) {
            print "\t$j\n";

        }
    }

##</code><code>##

33
	1
11
	4
2
	2

##</code><code>##

2
11
33