Initially hiring manager talked over the phone. Then a technical phone interview for about 45 mins. This was followed by a whole day onsite face to face interview (apx. 6 hrs), Several technical rounds with couple of interviews by managers. There were several C programming questions on data structure and algorithms. particularly few questions on trees. They went through my resume in great detail. There were some personality type questions too. e.g.. what will you do when someone comes with a problem when you are about to leave the office