Microsoft SDE Intern Interview Experience

Resume Screening

My resume was shortlisted through a LinkedIn referral.

---

Round 1 (60 mins – Fundamentals & Discussion)

The first round was largely conversational and focused on core CS fundamentals rather than heavy coding.

Concepts:-

I was asked about Linked Lists, including their real-world applications, how they compare with arrays, and in which situations one would prefer linked lists over arrays. This then transitioned into questions on HashMaps, where I was asked how they store unique elements internally and to explain the concept of hashing at a high level.

Coding:-

I was then asked- how to store elements uniquely. I suggested using a HashMap, after which a constraint was introduced—to solve it without using any additional data structure. We discussed alternative approaches, and I explained a sorting followed by linear comparison solution.

Overall, the round felt more focused on understanding trade-offs and different approaches rather than arriving at a single “optimal” answer.

---

Round 2 (Same Day– Design & Coding)

The second round started with a design-oriented problem involving users and groups.

The initial requirement was to design a data structure where:

• A user can belong to multiple groups
• We should be able to fetch:
  1. all groups a user belongs to
  2. all users in a given group

HashMap usage was initially not allowed.

I discussed multiple approaches- connected graph based approach, using adjacency representations, and reasoning about DSU. The emphasis was clearly on explaining design choices, complexity, and scalability. For every design suggested, cross-questions on its scalability were fired.

After the discussion, I was then asked to code the solution with HashMaps allowed. I focused on writing modular code while explaining my approach.

---

Overall Takeaway

The entire interview process was fundamentals-driven, with strong emphasis on data structure understanding, and design thinking. Microsoft values how well you can explain why a solution works just as much as how you implement it.