Learning JavaScript Data Structures and Algorithms - Third Edition

Removing a leaf node

The first scenario is a leaf node that does not have a left or right child ({9}). In this case, all we have to do is remove the node by assigning null to it ({9}). However, as you learned during the implementation of linked lists, we know that assigning null to the node is not enough, and we also need to take care of the references (pointers). In this case, the node does not have any children, but it has a parent node. We need to assign null to its parent node, and this can be done by returning null ({11}).

As the node already has the value null, the parent reference to the node will receive null as well, and this is the reason we are returning the node value in the method removeNode. The parent node will always receive ...