Hopper Software Developer interview questions

Did a coding challenge follwed by one hour google hangouts interview. Onsite was 4 rounds each an hour long. One of the interviewers gave no feedback and stared silently and would nod along as I explained my thought process. I got the impression in that round that they wanted to find my failure point rather than assess how good of a teammate I would make. Overall pretty unpleasant experience. I wouldn't recommend anyone interview here unless they wanted to take a free trip to Boston.

Started with a straight forward hackerrank challenge question that just about anybody could breeze by in 10 minutes - let alone the 30+ minutes that was given. Next interview was a much harder code challenge with a developer, they scheduled it 3 weeks after the hackerrank challenge, at that point I recognized I was probably wasting my time but I decided run with it in case they surprised me and more experience is good to have on these challenges anyway. They did not surprise me, the interviewer seemed so disinterested in the interview process it felt like he would rather watch paint dry. I definitely got the feeling from his groans and sighs he did not want to be there and he felt I was a waste of his time from the start.