Samsung Electronics Software Developer interview questions

For the 1st onsite interview, I need to finish a written C-Test. It took about 90 minutes. Then, 2 senior engineers asked me some technical questions (C++, Java), and some algorithm questions. For the 2nd onsite interview, I talked to 1 Director of RD and then a senior engineer. Same thing, C++/Java/Linked-list questions. For the 3rd interview, I talked to their VP of RD. Some C++/Java/Algorithm questions, even let me answer 2 questions at home(since I don't know the answer during the interview). But, it turned out, they still not giving me an offer.