The first round began with a discussion about my resume and internship experience. The interviewer then moved directly to a HackerRank coding problem based on the general concept of Publish-Subscribe (Pub-Sub). I approached the problem and successfully solved it using a different approach.

Following the coding round, the discussion shifted towards C++ and multithreading concepts. The interviewer asked several in-depth questions about atomicity, thread synchronization, and the use of queues in multithreaded environments. We also discussed the internal working of atomic operations, condition variables, and memory management.

The interview further covered core C++ concepts, including classes, inheritance, and object-oriented programming. Overall, the round focused heavily on problem-solving skills, practical understanding of multithreading, concurrency, and strong fundamentals of C++.