Transferring to UCSD Computer Science Pre-Math

I’m a community college student potentially interested in trying to transfer to UCSD with a major of computer science. I found a source online that says that computer science majors (pre-math) have an admit rate of 85% to UCSD. What does it mean to apply as a pre-math CS major, and how is it different from normally applying to the school?

Source: http://cacollegetransfer.com/2016/08/computer-science-admitted-transfer-gpa-by-uc/

https://www.universityofcalifornia.edu/infocenter/transfers-major may help you.

At UCSD, students not admitted directly to the CS major should not expect to be able to change into the CS major after enrolling.