#!/usr/bin/perl
use strict;
use warnings;

# There are different namespaces for scalars, arrays, and hashes
my $foo = "Hello World";
my @foo = ("Dog", "Cat", "Mouse");
my %foo = (1980, "Moscow", 1984, "Los Angeles", 1988, "Seoul", 1992, "Barcelona", 1996, "Atlanta", 2000, "Sydney", 2004, "Athens");

print "scalar: $foo\n";

print "array: @foo\n";

print "hash:\n";

my $key;
my $value;
while (($key, $value) = each(%foo))
{
  print "$key --> $value\n";
}