Amazon SDE-II | Phone screen round experience.

I began the interview with my introduction. The interviewer then presented a DSA problem: "Calculate sum of each subarray of size K for an array." I first outlined a brute-force solution and then proceeded to optimize it using the Sliding Window technique, clearly explaining the time and space complexity. I also re-iterated and dry-ran various edge cases to ensure the solution's robustness. I was not required to compile the code.

The follow-up question was to "Return max of each window instead of the sum." For this, I offered three distinct approaches:

1. For distinct elements, I suggested using a sliding window combined with a set to track window elements and a maxHeap to find the maximum. I explained how to handle heapPop() if the max element is no longer in the window.
2. For non-distinct elements, I proposed using a map instead of a set to maintain counts, ensuring heapPop() is done only when the count of the max element is zero.
3. As a more advanced option, I mentioned using a segment tree to efficiently store the array and query the maximum of each segment.

I thoroughly explained the time and space complexity for each of these cases.

Towards the end, I asked the interviewer a query regarding the typical range of work and responsibilities for this role. My expected verdict for this round is Inclined.