Another option is to take first semester course work at a community college, preferably one where USC has articulation listings (see USC:Transfer Planning Guide ). This may be a desirable option if you want to reduce the cost of your degree.
This is not a good idea, since CPSLO is on the quarter system, so course transferability may not work out too well (first quarter calculus will be like 2/3 of first semester calculus, for example).
Note that CPSLO will switch to the semester system, probably before you graduate if you decide to enroll there. But this coming academic year will be under the quarter system.