Based on the prototype descriptions, there's no separate structure for the first and last items on the list, or the equivalent using a dummy list item, so it's not a "normal" implementation of a linked list. Instead, part of the apparent point of this exercise is for the student to create programs to search for the first or last item, given a pointer to any item within the list. If your goal is to learn about linked lists, I'm not sure this particular thread (topic) would be a good one to use as an example.