my @nums = (1, 2, 4, 5, 8, 9);
my @dat =  (3, 9, 14, 10, 12, 8);
for my $i ( 0 .. $#nums ) {
    print "$nums[$i] $dat[$i]\n";
}

##</code><code>##

use List::MoreUtils qw(zip natatime);

my @nums = (1, 2, 4, 5, 8, 9);
my @dat =  (3, 9, 14, 10, 12, 8);
my $it = natatime( 2, zip(@nums, @dat) );
while ( my @vals = $it->() ) {
    print "@vals\n";
}

##</code><code>##

use List::MoreUtils qw(pairwise);

my @nums = (1, 2, 4, 5, 8, 9);
my @dat =  (3, 9, 14, 10, 12, 8);
print pairwise { "$a $b\n" } @nums, @dat;