my @ss =
  map sort_inner( [ keys %{ $_->[ 0 ] } ] ),
  sort { $a->[ 1 ] <=> $b->[ 1 ] }
  map [ $HoHoA{ $_ }, substr( $_, 3 ) ],
  keys %HoHoA;


for my $i ( 0..$#ss-1 ) {
  my $si = $ss[ $i ];
  for my $j ( $i+1..$#ss ) {
    my $sj = $ss[ $j ];

    for my $ki ( @$si ) {
      for my $kj ( @$sj ) {
        print "$ki - $kj\n";
      }
    }

  }
}

sub sort_inner {
  return [
          map $_->[ 0 ],
          sort { $a->[ 1 ] <=> $b->[ 1 ] || $a->[ 2 ] <=> $b->[ 2 ] }
          map [ $_, /\d+/g ],
          @{ $_[ 0 ] }
         ]
}

##</code><code>##

    for my $ki ( @$si ) {
      for my $kj ( @$sj ) {
        print "$ki - $kj\n";
      }
    }

##</code><code>##

for my $i ( 0..$#ss-1 ) {
  my $si = $ss[ $i ];
  for my $j ( $i+1..$#ss ) {
    my $sj = $ss[ $j ];

    # ...

  }
}

##</code><code>##

{ $a->[ 1 ] <=> $b->[ 1 ] || $a->[ 2 ] <=> $b->[ 2 ] }

##</code><code>##

my @ss =
  map sort_inner( [ keys %{ $HoHoA{ $_->[ 0 ] } } ] ),
  sort { $a->[ 1 ] <=> $b->[ 1 ] }
  map [ $_, substr( $_, 3 ) ],
  keys %HoHoA;

##</code><code>##

my @tmp =
  map $_->[ 0 ],
  sort { $a->[ 1 ] <=> $b->[ 1 ] }
  map [ $_, substr( $_, 3 ) ],
  keys %HoHoA;

##</code><code>##

my @ss = map sort_inner( [ keys %{ $HoHoA{ $_ } } ] ), @tmp;

##</code><code>##

sort_inner( [ keys %{ $HoHoA{ $k } } ] )