#!/usr/bin/perl

use strict;

use warnings;

my @aa=("aa", "bb", "cc");

print "@aa\n";

my $aa_num=@aa;

print "$aa_num\n";

my %hash = ("a"=>1, "b"=>2,"c"=>3);

my @k = keys %hash;

print "@k\n";

print "OK\n" if keys %hash == $aa_num;

aa bb cc

3

c a b

OK