On Removing the Pushdown Stack in Reachability Constructions [chapter]

Oscar H. Ibarra, Zhe Dang
2001 Lecture Notes in Computer Science  
A discrete pushdown timed automaton is a pushdown machine with integer-valued clocks. It has been shown recently that the binary reachability of a discrete pushdown timed automaton can be accepted by a 2-tape pushdown acceptor with reversal-bounded counters. We improve this result by showing that the stack can be removed from the acceptor, i.e., the binary reachability can be accepted by a 2-tape finite-state acceptor with reversal-bounded counters. We also obtain similar results for more
more » ... l machine models. Our characterizations can be used to verify certain properties concerning these machines that were not verifiable before using previous techniques. We are also able to formulate a subset of Presburger LTL that is decidable for satisfiability-checking with respect to these machines. « ÛÕ, where Û is the stack content and Õ is the state (we assume that the stack alphabet is disjoint from the state set). If Å is a PM and Ë is a set of configurations, define the
doi:10.1007/3-540-45678-3_22 fatcat:pleb3eqv5bhwzlwe7mdm2lo5x4