static VectorIterator create(std::vector<T> v) {return VectorIterator(v);}
VectorIterator operator - (int n) { return VectorIterator(_vector, _pos-n); }
static VectorIterator create(int init_size) {return VectorIterator(init_size);}
VectorIterator operator + (int n) { return VectorIterator(_vector, _pos+n); }