$ perl -wE'
my %a = (13 => 1, 19 => 1);
my %b = %a;
say keys %a;
say keys %b;'
1913
1319

$ perl -wE'
my %a = (13 => 1, 19 => 1);
my %b = (19 => 1, 13 => 1);
say keys %a;
say keys %b;'
1913
1319