I have checked the assist.org. It said the Electrical Engineering and Computer Sciences is offered in the College of Engineering, but the Computer Science is offered in the College of Letters and Sciences. The EECS major is ended up in a B.S degree, but the CS major is B.A degree. What is the difference between them? Which one is competitive? I am a transfer student.
Both are very competitive. You should ask in the Berkeley forum. Here is some info for the BA:
https://eecs.berkeley.edu/resources/undergrads/cs/transfer-prereqs
I believe that most of the UC CS programs are very difficult, or impossible, to complete in 2 years following transfer-I have heard that you can expect to take 3 years typically.