Bloomberg Software Engineer - New Grad interview questions

One of the R&D manager at Bloomberg contacted me through LinkedIn to apply for the role. The first round was a technical phone interview. The interviewer asked me about one of my project and how I designed it. He changed requirements, various scenarios and asked how I would adapt the design. Then a simple question on adding two very large numbers(using linked list). The next round was at their Princeton office a month later. Had two technical interviews. The first interviewer asked questions on Data Structures. Like complexities of various operations(insert, search, delete) on data structures like array, linked list, heap, stack, trees. Then questions on networking and operating systems. I had taken OS class more than an year back and didn't take any Computer network classes during my grad studies(the interviewer was surprised on this). Too bad not to revise them and messed up on these questions. Then a simple problem of opening and close bracket validation which I solved but didn't engineer well. The next round was about concepts of OOP, language design and garbage collection. I think my first round had already made a bad dent and the second round was over earlier than the interview of other candidates with me. After lunch, it was a small discussion of 5-10 min with the HR person with questions like what interests you in Bloomberg etc.