SDE-2 at Microsoft

How it went

What they would tell you

How to prepare

Round by round

1. 1

   Coding Round90 min

   I walked into the coding round feeling pretty confident. This was my comfort zone, solving algorithmic problems. The challenge presented was straightforward at first glance: Problem: You are given a sorted string, such as "aaabbbccccccceeee", and your task is to determine the frequency of a given character in the string. The catch was that the solution needed to be achieved in O(logN) time complexity and O(1) space complexity. At first, I felt the nerves creep in, after all, I had to come up with a solution that was efficient in terms of both time and space. However, as I started thinking through the problem, I relaxed and found the right approach using binary search to find the position of the character and calculate the frequency. I was able to solve it efficiently within the given time frame, and I was pretty satisfied with my performance.

2. 2

   System Design Round60 min

   I’ve always enjoyed tackling large-scale system design problems, so I saw this as a great opportunity to show what I can do. The problem? Design an Airline Booking System. This wasn’t your typical “design a system” question, it came with some real-world challenges. I had to think through things like:

   • The best way to implement flight search.
   • Which database would be ideal for storing flight data and why.
   • How to handle concurrent booking requests without any clashes.
   • Managing the cancellation flow, especially since payments are handled by third-party services.
   • And how to store search histories efficiently, particularly when multiple routes are available between two points. I really enjoyed diving deep into this problem. I walked through how to scale the system, weighed the trade-offs of different storage options, and considered potential bottlenecks. The interviewer seemed pleased with the system I came up with and the thought process I shared.
3. 3

   Performance Round60 min

   This round was a bit of a curveball. I was presented with a scenario where a user clicks a button, and suddenly, the UI freezes for one minute. I was asked to identify the potential reasons for this UI freeze and come up with solutions. I tackled both frontend and backend issues, discussing potential network bottlenecks, inefficient rendering, and possible backend delays. However, upon reflection, I realize I didn’t dive as deeply into possible performance optimizations as I could have.

4. 4

   Behavioral Round60 min

   This round was more about who I am as a person and how I approach work challenges. We talked about:

   • How I handled conflicts with team members.
   • A difficult project I worked on and how I overcame obstacles.
   • My leadership experience and how I balance technical responsibilities with team growth. I appreciated the fact that the interviewer didn’t just want to hear textbook answers. They were genuinely interested in how I worked, collaborated with teams, and navigated through difficult situations.

What came up