On the Relationship between Reachability Problems in Timed and Counter Automata
نویسندگان
چکیده
This paper establishes a relationship between reachability problems in timed automata and space-bounded counter automata. We show that reachability in timed automata with three or more clocks is naturally logarithmic-space interreducible with reachability in spacebounded counter automata with two counters. We moreover show the logarithmic-space equivalence of reachability in two-clock timed automata and space-bounded one-counter automata. This last reduction provides new insight into two problems whose precise computational complexity have independently been identified as open.
منابع مشابه
Relating Reachability Problems in Timed and Counter Automata
We establish a relationship between reachability problems in timed automata and spacebounded counter automata. We show that reachability in timed automata with three or more clocks is logarithmic-space inter-reducible with reachability in space-bounded counter automata with two counters. We moreover show the logarithmic-space equivalence of reachability in two-clock timed automata and space-bou...
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