pl@nereida:~/Lperltesting$ perl5.10.1 ./abigail1.pl
@- = (0, 0)      length of @- = 2        last - index = 1
@+ = (1, 1, )    length of @+ = 3        last + index = 2
pl@nereida:~/Lperltesting$ perl5.8.8 ./abigail1.pl
@- = (0, 0)      length of @- = 2        last - index = 1
@+ = (1, 1, )    length of @+ = 3        last + index = 2