Understanding deletion of last node

Deleting the last node in a doubly linked list is similar to deleting the first node. This is because we can access both the tail node and the previous pointer in each node. Let's go through all the cases we need to consider.

1. The list is empty

When the list is empty, meaning it contains no elements, any attempt to delete a node is unnecessary because there are no nodes in the list. Since there is nothing to remove, the list remains unchanged. We can return the existing tail, as the list is empty, and no node needs to be deleted.