BT Group Software Developer interview questions

Interview was tough. First round is screening round. I have applied via staffing agency. 1) 25 questions for aptitude(25 mins) 2) 35 java questions(90% of them were inheritance and multithreading related) The aptitude was very tough and its was the level of CAT. We have provided with a TAB where we have to take online test. They have 50 tabs only so others candidate have to wait for their turn. Might take 2+ hours. Very difficult aptitude and tough java question. Waiting for my result.