How can I insert/access/change elements from a linked list/hashtable/etc?
I’ll use an “inserting into a linked list” as a prototypical example. It’s easy to allow insertion at the head and tail of the list, but limiting ourselves to these would produce a library that is too weak (a weak library is almost worse than no library). This answer will be a lot to swallow for novice C++’ers, so I’ll give a couple of options. The first option is easiest; the second and third are better. • Empower the List with a “current location,” and member functions such as advance(), backup(), atEnd(), atBegin(), getCurrElem(), setCurrElem(Elem), insertElem(Elem), and removeElem(). Although this works in small examples, the notion of a current position makes it difficult to access elements at two or more positions within the list (e.g., “for all pairs x,y do the following…”). • Remove the above member functions from List itself, and move them to a separate class, ListPosition. ListPosition would act as a “current position” within a list. This allows multiple positions within th
