Cloud Lending Solutions Salesforce Developer interview questions

Repeated unwanted questions on Data Structure for a job profile in salesforce. Despite clearing two technical rounds and being asked to wait for an HR round, i was told HR wasnt sure and a new technical round was added in between. Which again was repeated irrelevant questions on data structures which were pretty annoying. please have your interviewee know something about the technology before allowing them to take an interview. Despite managing to give a good interview I didnt get any offer rolled out.