Looks good to me. You are right, it's hard to say what's going wrong when nobody gives feedback. Often if you do well on 4 problems and then tank the 5th, that

Looks good to me. You are right, it's hard to say what's going wrong when nobody gives feedback. Often if you do well on 4 problems and then tank the 5th, that can be enough to miss out. I think if you can regularly solve this difficulty of problem you should be able to get a job though. Would you mind emailing me whatever resume-ish stuff you have at my hn username at gmail? Maybe I can give more specific help.