Case study: Lowest common ancestor

May 1, 2020

Introduction

It is the first interview I got the whole week. I worried about interviewing.io financial situation, and free anonymous interview is no longer affordable since some one has to pay the bill. A lot of layoffs last two months, people are flooding in job market for software engineer positions.

Mock interview case study

Here is the code.





Discussion we had on the mock interview:

The clever part is to return two things in recursive function. One is to find lowest common ancestor, if it is found then it should be returned; Second one is supporting role to calculate the node found. As we know, the node can be root node or any child node in binary tree. Using total nodes found is the technique to make it easy to identify the edge case: root node is one of nodes p or q, then another node is in subtree nodes.

One thing to make it more readable is to replace checking of return TreeNode null with node's count comparison to value 2 instead.

Interviewer feedback

Interviewee - an ex-facebook engineer

His second algorithm is also bug-free, here is the link.

Actionable items

May 25, 2020

The interviewee is young and top talent engineer. After the mock interview, he saw my feedback, and then he decided to get connected on interviewing.io. I should ask a linkedin.com connection from him, so I can track his career success later on.

One tip a time - system design reading website

Here is the link.

One tip a time - system design website

April 10, 2020

Introduction

It is so challenge for me to push myself to learn better about system design. One of actions is to work as a system design interviewer on interviewing.io. I started to learn my weakness about communication, I have chance to interview best engineers and learn how they approach problems.

One tip a time

I have chance to interview an engineer who works for FANG company. I asked him to share me his tip to prepare system design.

Here is the link. 

Case study: Find the longest length of substring containing distinct characters

April 5, 2020

Introduction

It was my April 5 6:00 PM mock interview as an interviewee, and I had chance to work on the algorithm, and was able to perform analysis and coding in 45 minutes. The interviewer was the manager in Financial industry in New York area, he have a lot of interview experience. I like to write a short case study on my mock interviews.

Case study

Here is my gist.

Code is displayed in the following:

I also like to share the feedback from interviewer and my feedback as an interviewee as well.