Bloomberg Graduate Software Engineer London interview questions

I applied online through their website. I was invited to a phone interview in which I was asked a variety of questions about Java, O-O principles, differences between Java and C/C++, inheritance, polymorphism, garbage collection and the like. Finally I was asked to solve a coding question on hackerrank. I passed the interview and I was invited for an onsite interview in London. I was interviewed by three people at once, two of them asked one question each. I was sent home after one hour. What disappointed me was that they sent me an automated email where they said they will not take my candidacy further, giving zero feedback. After two interviews.