Status : 2021 Grad (BTech in CSE from Tier-2 college)
Position : SDE1 at American Express
Location : Bangalore
Date : 3 Jan, 2022 - 18 Jan, 2022 (All 4 Rounds)

I took a referral from my friend who is already working at Microsoft, so I was directly called for an interview. HR contacted me and told me that I'll have 3 technical rounds first.

Round 1 (Technical)

The interviewer was a SDE II from Microsoft, USA.
Initially she asked me to introduce myself. Then she asked me about the project I'm working upon in my current firm. Then she asked me to explain any one project which I did in my college days.

Then, she asked me the following behavioural questions ::
Q1 : Tell me about a time when you faced a challenge in your life and how did you overcome it?
Q2 : Tell me about a time you innovated something

Coming to the coding part, I was asked to share my screen and code the following problems on my local IDE ::

1. https://leetcode.com/problems/two-sum/ : Solved
2. https://leetcode.com/problems/partition-equal-subset-sum/ : Solved using recursion [I was thinking that she will ask me to optimize it but she didn't, instead she asked me to write test cases for the code]
   Then I was asked to tell the Time and Space Complexity of the solutions I provided.

The interviewer was nice and at last told me about the team and the products they work upon.

Round 2 (Technical)

The interviewer was a SDE II from Microsoft, USA.
Again, she asked me about the project I'm working upon in my current firm first. Then she directly jumped upon the question part.

It was a pretty long story, kind of designing a system for money exchange. However, the question ultimately comes down to Finding the lower and upper bound of a number in a sorted array.

I gave her both Linear and Binary Search solution. Then she asked me to tell the complexity of both and code the binary search solution.

I think she wanted to see how I used OOP principles to solve the question. However I was stuck in a corner case, which I eventually solved at the end.

The interviewer was having another meeting so she left after this.

Round 3 (Technical)

The interviewer was a Senior Engineer from Microsoft, USA.
Yes you guessed it right, again they asked me about the projects I've worked upon in my firm and my college days, cross questioned me a few things, and then jumped on the problems part.

Then I was asked the following coding questions ::

1. https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
2. https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/
3. https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/
4. https://leetcode.com/problems/all-nodes-distance-k-in-binary-tree/

I wasn't asked to code the first two questions, for others I gave the optimal answer. Then he asked me the time and space complexity of all the solutions.

After 3-4 days, I got a call from the HR that I have another Round (Technical + Managerial).

Round 4 (Technical + Managerial)

The interviewer was a Principal Software Engineer from India (I guess 18 years experience).

No coding question was asked in the complete round, however he asked me small small questions from different subjects. Some of them I remember were:

1. Initially he asked me about the project I'm working upon currently
2. Then he asked me the project I did in my majors
3. If you're given a problem, how will you choose the programming language in which that problem should be solved?
4. What qualities should a software engineer have? Which one is the most important to you and why?
5. Let's suppose you're given a task to code a washing machine, which language will you choose?
6. There is a client, sitting in the space and the server is here in India, the client is taking picture of the space and sending it to the server. How will you implement a system like this?
7. What is DevOps?
8. What is OOPS? How will you explain it to a non-technical person?
9. Tell me about a technology update you've heard of in the last month.
10. What according to you are Distributed Systems?

Not sure if my answers were correct, If someone knows the right answer to Q6 please let me know.

My Overall Review:

1. The in-depth knowledge of DSA concepts is must. [Eg: you should know how the time & space complexity of your overall solution is coming rather than just jumping to the complexity]
2. Once scheduled the interview process is really smooth, the interviewers are polite and they help you if you get stuck.

Keep Hustling!