// Given the head of a linked list, we repeatedly delete consecutive sequences of nodes that sum to 0 until there are no such sequences. // After doing so, return the head of the final linked list.

IDG. Figure 1. Traversing a doubly-linked list forward and backward. CRUD operations in doubly-linked lists. Creating, inserting, and deleting nodes are all common operations in a doubly-linked list.

* Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.

IDG. Figure 2. The initial singly linked list consists of a single Node (A) This operation has a time complexity of O(1)–constant. Recall that O(1) is pronounced “Big Oh of 1.” (See Part 1 ...