Minimum Window Substring: A Step-by-Step Interview Walkthrough
Minimum Window Substring is the problem that separates people who've used sliding windows from people who understand them. Most candidates have seen a window expand and contract on simpler problems, but this one forces two harder questions at once: how do you efficiently check whether the current window contains everything you need (including duplicates), and how do you know when to expand versus when to shrink?
9 hours ago15 min read
Kruskal's Algorithm: A Step-by-Step Interview Walkthrough
Minimum Spanning Tree problems are a staple of technical interviews because they sit at the intersection of greedy reasoning and the Union-Find data structure — two things interviewers love to test together. The signal here is whether you understand greedy correctness and can apply Union-Find fluently, not just whether you can recite the steps.
Jun 1011 min read
Cheapest Flights Within K Stops: A Step-by-Step Interview Walkthrough
Cheapest Flights Within K Stops is a problem that looks like a routine shortest-path question, but it quietly adds a twist that breaks the standard tool. The signal interviewers want is whether you can recognize when a familiar algorithm's assumptions are violated and reach for the right variant instead of forcing the wrong tool.
Jun 1013 min read
