While explaining the problem Initially he said, we are looking only for logic, but in the end he said "try to write syntactically correct upto semi colons". which was surprising! I tried my best to write the program as well as conveyed the fact that I don't use these constructs daily. I also showed in the program where I might have put wrong syntax as I don't remember it completely. But I made sure to explain the logic. However in the end, I think I wasn't able to convince the interviewer. I sincerely felt I was poorly judged, and with due respect, interviewer was not appropriately experienced to interview senior guys and was judging people just by the book knowledge and syntax.