Why can't I add pointers?

Question

I have code very similiar to this:

LINT_rep::Iterator::difference_type LINT_rep::Iterator::operator+(const Iterator& right)const
{
    return (this + &am         


        

Answer 1

742 Evergreen Terrace + 1 = 743 Evergreen Terrace

742 Evergreen Terrace - 1 = 741 Evergreen Terrace

743 Evergreen Terrace - 741 Evergreen Terrace = 2

743 Evergreen Terrace + 741 Evergreen Terrace = ???