C3 AI Software Engineer interview questions

I did some hackerrank test and a behavioral call. Afterwards no one ever got back to me, not even telling me that I failed. Poor communication from the company and no motivation given for rejection.

Extremely long interview process just to get auto-rejected after an on-site interview without any feedback even though I emailed the recruiter twice politely asking for a feedback. Took OA, one technical phone screen, and 3 45 minute on-site back-to-back interviews. I was able to give the correct, optimized solutions for all three. Immediately after the interview, I sent an email to the recruiter thanking the recruiter and the interviewers for their time and never heard a single reply since. Never had a problem communicating with the recruiter before, he was very understanding. However, it is extremely disrespectful to just send me an automated email after this long process. Moreover, one interviewer from on-site called sick day but he was still interviewing me. This really shows the quality of this company and how unprofessional and inefficient the hiring process is. Ridiculously long for no reason for a company like this.