# Read in test data.
while (<DATA>) {
    my ( $k1, $k2, $v ) = split;
    $hash{$k1}{$k2}[0] = $v
}

# Make an array of all key pairs.
my @key_pairs;
foreach my $k1 ( keys %hash ) {
    foreach my $k2 ( keys %{$hash{$k1}} ) {
        push @key_pairs, [$k1, $k2];
    }
}

# Sort key pairs
my @key_pairs_by_value = sort { 
    $hash{ $b->[0] }{ $b->[1]}[0]
    <=>
    $hash{ $a->[0] }{ $a->[1]}[0]
} @key_pairs;

# print sorted
for my $keys ( @key_pairs_by_value ){
    my ($colour, $device) = @$keys;

    printf("\n%-55s %-55s %-40s",
          $colour, $device, $hash{$colour}{$device}[0]  );
}