#!/usr/bin/perl -w
use strict;

my @elems = ("x", "y", "z");
my @tobepopulated;
push @tobepopulated, "foo" for (1..10);

my $cnt=0;
my @new_array = map { $_ . "-" . $elems[$cnt++ % @elems] } @tobepopulated;

print join "\n", @new_array;