COMPLETENESS AND NON-COMPLETENESS RESULTS WITH RESPECT TO READ-ONCE PROJECTIONS

Several models of restricted branching programs or binary decision dia grams have a lot of applications in hardware verification. These model s are investigated here from a complexity theoretical viewpoint. Becau se of depth restrictions projections are not suitable as reduction typ e and have to be restricted to read-once projections. Several types of polynomial-size binary decision diagrams have complete problems with respect to polynomial read-once projections. On the contrary it can be proved that the classes of polynomial-size decision trees and polynom ial-size read-once branching programs or free binary decision diagrams do not have such complete problems. (C) 1998 Academic Press.