sub print_with_ands {
  my $x=0;
  my $a=shift;
  printf "$a->[$x-1]%s",
    defined $a->[$x+1] ? ", " : 
    ! defined $a->[$x] ? "\n" : 
    $x==1 ? " and " : ", and " 
    while defined $a->[$x++];
}