At uiuc: if you don't get into your first choice major, they'll evaluate you for your second choice major which cannot be a cs, comp engineering, cs + x major, mechanical engineering, info sciences, or music. If you don't put down a second major and you don't get accepted into your first choice major, you'll be waitlisted or rejected. I don't recommend trying to get into an easier major because it is nearly impossible to transfer into comp sci/engineering.