Once you have the list that you want to print; you don't need to use a joinjoin, instead you can just print it with $, set appropriately. $, is also known as $OFS and
$OUTPUT_FIELD_SEPARATOR; use perldoc perlvar.
This can be much more efficient even with small lists.
my @arr = ( 1, "Ali", 2, "Bobbi", 3, "Charli" );
local $, = " ";
print @arr, $/;