How to clone a graph without copying a node twice
5 min read A deep copy of a graph only works if you record each clone the moment you make it, before you ever touch its neighbors. Read article
Coding Interview Questions
Coding Interview Questions
Designing an LRU cache that actually runs in O(1)
7 min read Why LeetCode 146 forces a hash map paired with a doubly linked list, how to code it cleanly, and where the LFU and TTL follow-ups go. Read article
Coding Interview Questions
Two Sum, and the hash-map habit it’s really testing
6 min read Two Sum looks trivial, but the jump from the brute-force pair check to the one-pass hash map is the exact skill interviewers are screening for. Read article
