Obtain the backmost node, and remove it from list too. Moves node to front of list. Moves node to back of list. Moves node to front of list. Moves node to back of list.
Removes node if it's in list.
Obtain the backmost node. Obtain the frontmost node. Obtain the backmost node, and remove it from list too. Get the next node of this list. Get the previous node of this list.