my @nums = (17, 10, 20, 33, 30, 40, 10, 33, 40, 15, 16, 17);

##</code><code>##

my %unordered = map { $_ => undef } @nums;

##</code><code>##

my @un_nums = join " ", keys %unordered; 

##</code><code>##

print "@un_nums\n";

##</code><code>##

my @array1 = (1, 2, 3, 4, 5);
my @array2 = ("1 2 3 4 5");

print "@array1\n";
print "@array2\n";