Interview Problem Walkthroughs | Daniel Greener-Vigil

Classic coding interview questions solved multiple ways, with real complexity analysis and production-quality code.

June 19, 2026· 4 min read

Detecting a Cycle in a Linked List: Floyd's Tortoise and Hare

Two pointers, one slow and one fast, are all it takes to detect a cycle in a linked list in O(1) space — no hash set required. Here's why it actually works, not just that it does.

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Interview Problem Walkthroughs

April 17, 2026· 6 min read

Reversing a Linked List — Iterative and Recursive, With Diagrams

Reversing a singly linked list two ways, with a real explanation of the pointer surgery involved — plus why the elegant recursive version isn't always the right answer.

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Interview Problem Walkthroughs

February 13, 2026· 9 min read

Two Sum, Three Ways: Brute Force, Hash Map, Two Pointers

The classic first interview question, solved three different ways — with a real explanation of why the hash map approach wins and when the alternatives are actually the better call.

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