#!/usr/bin/perl

use strict;
use warnings;


my @arr1 = (1,2,3,4);
my @arr2 = ();

print ((@arr1) ? "arr1 is defined\n" : "arr1 is not defined\n");
print ((@arr2) ? "arr2 is defined\n" : "arr2 is not defined\n");


my $arr_ref1 = [11,22,33,44];
my $arr_ref2 = [];


print (($arr_ref1) ? "arr_ref1 is defined\n" : "arr_ref1 is not defined\n");
print (($arr_ref2) ? "arr_ref2 is defined\n" : "arr_ref2 is not defined\n");


print (($arr_ref1->[0]) ? "arr_ref1 is defined\n" : "arr_ref1 is not defined\n");
print (($arr_ref2->[0]) ? "arr_ref2 is defined\n" : "arr_ref2 is not defined\n");


##</code><code>##

arr1 is defined
arr2 is not defined
arr_ref1 is defined
arr_ref2 is defined
arr_ref1 is defined
arr_ref2 is not defined