the concepts of s and sn programs are given by davis, weyuker, 1983. several parts of the complexity theory are carried out directly for s and sn programs. the concepts of non-deterministic and deterministic computation from s-programs are defined, and deterministic simulation of non-deterministic computation is proved. a universal 5-program for general (non-deterministic) computation is shown to require only one duplicate line label. complexity results are given for these and other simulations, e.g. turing machine by 5-programs and the reverse. cook's theorem for sn programs is proved in full.