my %hash;

map { push( @{ $hash{ $values{$_} } }, $_ ) } keys %values;


##</code><code>##

while(my($k,$v)=each%values){push@{$hash{$v}},$k;}


##</code><code>##

map{push(@{$hash{$values{$_}}},$_)}keys%values;


##</code><code>##

for my $key (reverse sort keys %hash) {

    print "Level $key:\n", join(", ", @{$hash{$key}}), "\n\n";

}