void main() {
ADT.Sequence a = ADT.Sequence(10);
a->add("aaa");
a->add("bbb");
a->add("ccc");
ADT.Sequence.SequenceIterator iter = a->first();
while(iter->has_next()) {
    iter += 1;
    write(iter->value() + "\n");
}
}

outout:
0
0
0
0
0
0
0
0
0
aaa
bbb
ccc
0