Microsoft Software Engineer Interview Questions

I would start with the simple two-pointer approach from both ends of the string. While the left and right pointers move inward, I compare characters and stop as soon as I find a mismatch. If the problem includes punctuation or spaces, I would clarify whether I need to ignore them before I code the solution. The reason I choose two pointers is that it is O(n) time and O(1) space, which is very efficient. I would also mention edge cases like empty strings, one-character strings, and odd versus even length.

I would first think about sorting the array and then scanning adjacent values, which is straightforward but costs extra time. To optimize it, I would use a hash set to track seen values and a second set for duplicates if I need to return each duplicate once. If the array is constrained to a known range, I might also mention using index marking or counting in place. The reason I choose a hash set is that it keeps the solution simple and gives O(n) time. I would also mention edge cases like negative numbers, repeated duplicates, and whether the output should preserve order.

I would first think about checking every possible subarray, but that is too slow. To optimize it, I would use Kadane's algorithm, where I keep track of the best subarray ending at the current position and the best result overall. The reason I choose this approach is that it naturally handles negative numbers and runs in O(n) time with O(1) space. I would also mention edge cases like all-negative arrays, where the answer is the largest single element. If asked, I could also explain the dynamic programming interpretation.

Before designing it, I would clarify whether this is for personal calendars, team calendars, or a shared booking system with conflict rules. At a high level, I would store events in a database with time ranges, owners, attendees, and recurrence information, then expose APIs for create, update, delete, and search. I would need a strategy for conflict detection so overlapping events are handled correctly, especially for rooms or resources that cannot be double-booked. The reason I would split event storage from notification delivery is that reminders, emails, and sync updates should not block the main write path. I would also talk about time zones and recurring events because those are common sources of bugs.

I would first think about storing nodes from one list in a hash set and then scanning the other list. That works, but if I want a more elegant solution, I would use two pointers that switch heads when they reach the end, so both pointers travel the same total distance. If the lists intersect, the pointers will meet at the intersection node. The reason I choose the two-pointer technique is that it uses O(1) extra space and is easy to explain once you understand the path-length alignment trick. I would also mention edge cases like no intersection and lists of very different lengths.