Prerequisites Computer Science 201 and either Computer Science 202 or Mathematics 236. Ondich, Staff CS 254 Computability and Complexity An introduction liense the theory of computation, graduated drivers license programs. What problems can and cannot be solved efficiently pfograms computers. What problems cannot be solved by computers, period. Prerequisites Computer Science 111 and either Computer Science 202 or Mathematics 236. Rafferty CS 257 Software Design It's easy to write a mediocre computer program, and lots of people do it. Good programs are quite a bit harder to write, and are correspondingly less common.