       &lt;---+ Third node
   |                            .
   |                            .
   |                            .
   |  pointer to node N-1                  pointer from node N-1
   |       |                                          |
   |       |     +------------------------------+     |
   +---&gt;   +---- |  Backward pointer            | &lt;---+ Final (Nth) node
                 +------------------------------+
                 |  Forward pointer             | ----&gt; NULL
             