use 5.17.6;
use strict;
use warnings;

my %a = (
    z => 1,
    y => 2,
    x => 3);

foreach (1..3) {
    print join(",", keys %a), "\n";
    print join(",", values %a), "\n";
    while (my ($d,$e) = each %a) {
        print "$d = $e\n";
    }
}