perhaps a better way of looking at it is how hard it will be to get a 3.3.
Here is the grade distribution from CS61A in fall 2014.
https://schedulebuilder.berkeley.edu/explore/courses/FL/2014/320
(make sure to uncheck previous years if you just want last years)
Total students is 1044.
Distro is as follows:
A+: 45
A: 173
A-: 138
B+: 241
Total A+ through B+: 597
B and below: 447
597/1044 = 57%
57% of people taking it got 3.3+ for that course. Of course this includes EECS people - if you made the assumption all EECS students got B+ or higher, and all non-EECS students were CS majors, both of which may not necessarily be true, then 597-300 = 297 CS students with a B+ or higher.
When you exclude EECS students you get 297/(1044-300) = 40%. Which is not too bad.
Also, according to the CS61A website, the grading scale is absolute, not relative to how well others do.
Taken from the CS61A course website: “This grading formula implies that there is no curve; your grade will depend only on how well you do, and not on how well everyone else does.” from http://cs61a.org/about.html
so no worrying about competition.
Also keep in mind many people taking 61A might not be majoring in CS:
“While some of the increased demand is linked to the growth of the computer science major, these courses also increasingly appeal to those outside the major, as computer literacy is “increasingly viewed by undergraduates as a core academic and professional competency,” the report said.”
from http://www.dailycal.org/2013/09/02/increased-cs-course-demand-leads-to-overflowing-auditorium/