Microsoft SDE-1/2/SDE-Intern Interview Questions | Kumar K | 14th December 2025 |Set 50

Question

My interview for the Microsoft SDE-1 role, and I believe I missed the opportunity.

Interviews

I had Round 1 (DSA) where I solved the first problem using recursion with memoization, but I forgot to add visited tracking. Due to internet fluctuations and limited time, the interviewer said he understood my intuition and moved on to the next question.The second question was Stock Buy and Sell. I explained that I would use a greedy approach: buy at a lower price, sell at a higher price, keep track of the minimum price so far, and update the maximum profit accordingly. When the current value is greater than the minimum price, I sell, add the profit to the answer, and update the minimum price. This approach runs in O(n) time. The interviewer seemed satisfied and, during feedback, advised me not to overcomplicate the solution but to think simply and break the problem into smaller parts.

 

Round 2 (System Design), I was asked to design a cache similar to an LFU cache. Initially, I got confused with LRU, but after asking clarifying questions, I understood the problem. The interviewer then asked me to design it with O(1) time complexity for all operations. I could not immediately derive the full O(1) solution and proposed a single doubly linked list with a hash map, which would require O(n) time for some operations. Due to internet issues and very limited time, I implemented only the get operation. The interviewer seemed satisfied with my approach, and afterward explained that the optimal solution would use two linked lists along with a hash map to achieve O(1) operations.

 

"Not sure what should I expect deep down I think I managed it well but my negative side waiting for rejection"