How is end() implemented in STL containers?

Question

So when we need to traverse a container from start to end we write something like

for (i = v->begin(); i != v->end(); i++)

assuming i

Answer 1

STL ensures this behavior by always storing stuff like this:

In the end (pun), it doesn't matter what end() is, as long as it's always end() (and, obviously, can't be confused with any other node).