use warnings;
use strict;

# my ($a,$b)=(0,0);

use List::MoreUtils qw/pairwise/;
my @a = (1 .. 5);
my @b = (11 .. 15);
my @x = pairwise { $a + $b } @a, @b;   # returns 12, 14, 16, 18, 20

use Data::Dump;
dd \@x;