I recently gave interview rounds at Microsoft for Senior Software Engineer position. Following is the interview experience I had after clearing the online HackerRank test. All the rounds happened on same day.

Round 1(DSA): Find the length of the longest sub-array whose elements sum to a value less than or equal to k. A sub-array is defined as a continuous block of elements from the original array.

After seeing the question and spending couple of minutes I told the interviewer that handling -ve values will be a different approach altogether. I was asked to code first only for the positive values. Did that perfectly.

Follow-up, how to handle input with negative values. IMO this was the turning point for the question and it took me somewhat significant amount of time to revamp the previous algo. I was only able to tell the approach and not able to code it up as time was over.

Round 2(LLD): Design Database SDK supporting multiple databases and multiple kinds of authentication to connect to those databases. Basically, you need to create this client side SDK and the client should be able to use it to connect to their respective databases in their application.

Standard followup like handling concurrency, handling different types of auth mechanisms, etc.

Round 3(HLD): Design a stock market status service which would show aggregated data and a list of top gainers and losers stocks. Aggregations are based on time durations, market valuation type, and sectoral index type.

Round 4(HM): Typical behavioral questions and counter questions on current work. Dive deep on current project and some basic HLD concepts questons.

Verdict: Will update. I have high hopes but don't know what's planned as per my luck.