Pointer Manipulation and Placeholder Nodes
Understand core linked list operations by mastering pointer manipulation and the use of placeholder nodes. This lesson teaches how to prevent common bugs linked to pointer ordering and edge cases, helping you write reliable and polished solutions for coding interviews in C++.
Most linked list bugs come from one of two places: a pointer that was moved before the next node was saved, or a solution that breaks on an empty list or a single-node list. Pointer manipulation fundamentals address the first. Placeholder nodes address the second. Together, they cover the majority of what goes wrong in linked list interviews.
Interview lens: Interviewers use linked list problems to see whether we manage state carefully under pressure. A candidate who reaches for a placeholder node without being prompted, and who saves a pointer before reassigning it, signals strong fundamentals. These are habits that separate polished solutions from ones that need fixing.
Pointer manipulation fundamentals
Pointer manipulation in linked lists comes down to a small set of moves that appear in almost every problem: saving a pointer before reassigning it, advancing a pointer to the next node, and rewiring connections ...