【perl】散列表的遍历

my %hash;
$hash{"objA"}{"size"}="ewr";
$hash{"objA"}{"width"}="werwer";
$hash{"objB"}{"size"}="ewasdr";
$hash{"objB"}{"width"}="werweasdr";

foreach my $k (grep {/^obj/} keys %hash) {
        print $k,"n";
        foreach my $subk (keys %{$hash{$k}}) {
                print "$hash{$k}{$subk} => $hash{$k}{$subk}n";
        }
        print "n";
}