use strict;

my %currency;
$currency{northamerica}{America} = "US Dollar";
$currency{northamerica}{Canada} = "Canadian Dollar";
$currency{asia}{Japan} = "Yuen";
$currency{asia}{China} = "RMB";

foreach my $continent (keys %currency) {
	foreach my $country (keys %{$currency{$continent}}) {
		print "in $continent/$country, people use $currency{$continent}{$country}\n";
	}
}