The tree round on my first onsite was Root to Leaf Paths. Enumerate every root-to-leaf path in a binary tree. Looked easy. The recursion took about four minutes to write. Running it on the sample input came back with a list where every path ended at ...

Solving problems related to data structures and algorithm has become the norm of many technical interviews in recent times. So whether you are a beginner or seasoned developer, it is important you keep your problem solving skills active. In this art...

The first time an interviewer asked me to walk through an LR rotation on a whiteboard, the four-case table was memorised cold. LL, RR, LR, RL. The interviewer drew three nodes, asked which case it was, and the answer came out fast. Then they asked: "...

It took an LRU Cache interview for me to realise the complexity table wasn't answering the real question. I'd been picking between arrays and linked lists for years before realising the table wasn't the answer to the question. Then LRU Cache came ...

There's a common piece of advice: "Want to write better code? Read good code." Sounds obvious. Rarely practiced. The problem is that most open-source projects are mazes. You open a repo, see 200 directories, and close the tab. Kubernetes is two mi...

A few years ago I solved 200 LeetCode problems and still froze on Mediums I hadn't seen. The breakthrough wasn't another hundred problems. It was a different loop. A problem asks for the longest substring with at most K distinct characters. You've s...