Don't go waste of time nearly 3 rounds u have to perform well in all those rounds.Out of 500 people they will select 50 people's for second round and 15 people's for 3rd round and they will hire only 3 members.1 round is of apptitude and 2 round is test case and puzzle and group discussion u have to perform well in those rounds to get selected for the 3 round.And 3rd is of puzzles and face to face interview and HR interview 60% of memebers will be shortlisted here