Trailing Pointer Technique

In the course of an insertion, it is often convenient to have two pointers into the list. Suppose that an insertion will occur in between node A and node B; then it would be handy to have a pointer to both nodes.
When searching the list for the correct point to insert, the leading pointer is looking for B, while the trailing pointer is one behind the lead. The A pointer will be needed to redirect the next pointer of A. The B pointer will be the next of the inserted node.
This is less likely to be used in a doubly linked list than a singly linked list, since the singly linked list may only move in one direction.
An example of this is given in a later slide show.

Links:
Straight Linked Lists
Circular Linked Lists
List Types