IBM Software Engineer interview questions

I was referred by my friend who has interned in IBM. Before that I already submitted my CV to their online recruitment system, but I seriously doubt there's any use of it. There's a 1 hour phone screen with 2 interviewers at the same time. They asked some simple coding and behavioral questions. After that they're interested enough to invite me to on-site interview, but I still have to push them a bit because my other interviews were around the corner and I had to schedule them quick. I was invited to the IBM Watson office. At IBM almost every employee has a separated office room, so I just met every interviewer at his own office. The interview started early and there're about 8 interviewers (I lost count and they didn't send me the schedule either), each last for 1 hour except the one who took me to lunch, so the entire process is actually quite tiring. 1 week later I sent a follow-up mail to the HR but only got silence. Then after another 2 weeks I sent another follow-up mail to the manager and some interviewers and finally heard from them that I'm no longer considered.

One phone screening with hiring manager, and then another phone interview with a member of the team. After that they send me th IPAT test. After one one week I got an offer for an onsite interview. The process was good and mostly about check your personality. Very basic Algorithms and Data structure questions and C++. Offer came after 2 weeks.