I recently got an offer from Microsoft. LeetCode discuss and company tagged questions were the biggest help I had in my preparation. Now it's time to give back a little :)
I reached out to multiple hiring managers on LinkedIn using inMail messages (yes I purchased premium for my job search). For about 1.5 months I had not heard back anything from Microsoft but on a random day one of the recruiters emailed saying they would want to interview me for an SDE-2 position. I had applied to that job-id and had reached out to the corresponding hiring manager on LinkedIn a month before.
Round 1 (Phone Tech Screen) - Interviewer initially asked about what I do in my current role etc. Then came the coding questions-
1) Shift all zeroes to the start of an array. Similar to this but not completely same - https://leetcode.com/problems/move-zeroes/ . I gave a brute force O(n^2) solution first and then optimized to O(n).
2) Meeting Rooms 2 - https://leetcode.com/problems/meeting-rooms-ii/. Gave the optimized solution.
3) Given a list of word synonym relations, determine if 2 given sentences are equal- https://leetcode.com/discuss/interview-question/698670/google-phone-screen-sentence-similarity-variant-june-2020-reject. Gave the perfect solution using disjoint set/union find. Did not have to write full code just the union find part.
For every question we discussed time and space complexity.
Round 2 Virtual Onsite Interview
Innterviewer had very specific questions about my resume, some of which I answered cleanly and some I faultered. The coding question he asked was to create an insert and delete function for an array. Then extended it to circular array. The trick here was to foresee a scenario of multithreaded application where those 2 functions can be accessed by 2 different threads (RACE CONDITION!!!). While I did not foresee it, when the interviewer said "what if it's a multithreaded application", I quickly said what could go wrong and how we can solve it. I did not completely implement the 2 functions, the interviewer kept changing requirements in between and I couldn't figure out what I was expected to do in some of the stuff he kept changing.
Round 3 Virtual Onsite Interview
Again a few questions on my resume and then coding questions-
1) Validate palindrome by deleting only one element - https://leetcode.com/problems/valid-palindrome-ii/. Gave the optimized approach. Wrote full code, dry run. Gave test cases and discussed time and space complexity.
2) Number of Islands - https://leetcode.com/problems/number-of-islands/. Gave BFS solution. Explained why I want to use BFS rather than DFS -easy to read and understand in future. Wrote full code, dry run. Gave test cases and discussed time and space complexity.
Round 4 Virtual Onsite Interview
Asked a few questions on multiprocessing and multithreading. Moved on to coding questions-
1) populate next pointer in a binary tree - https://leetcode.com/problems/populating-next-right-pointers-in-each-node/. Again explained why I want to do BFS (level order traversal using queue) over DFS. Space and time complexity explanation. Came up with good test cases to test the solution.
2) He asked number of islands again- I told him I did the same thing in the previous interview.
He then asked Sum of 2 Linked Lists- https://leetcode.com/problems/add-two-numbers/.
Round 5 Virtual Onsite Interview
This was the as appropriate interview. He asked me a Hard question. I still cannot find that question on leetcode and I cannot even explain that question here. It was pretty tough, I could not solve it. Gave some brute force solution. Wrote a bit of code and walked through it. Then the interviewer helped me through the question and we came up with a partial solution.
Hiring manager called me 2 days after my interviews and told the role I was being hired for (SDE 1) and in a couple of weeks I had the offer.
Regarding behaviour questions- Every interview will have them. Go over their company principles, show examples of how you have followed those principles before either in your college or work experience. Always follow the STAR method to answer those questions.
Total years of exp: 2