Improved upper bounds on synchronizing nondeterministic automata |
| |
Authors: | Zsolt Gazdag, Szabolcs Iv n,Judit Nagy-Gy rgy |
| |
Affiliation: | aEötvös Loránd University, Budapest, Hungary;bUniversity of Szeged, Szeged, Hungary |
| |
Abstract: | We show that i-directable nondeterministic automata can be i-directed with a word of length O(2n) for i=1,2, where n stands for the number of states. Since for i=1,2 there exist i-directable automata having i-directing words of length Ω(2n), these upper bounds are asymptotically optimal. We also show that a 3-directable nondeterministic automaton with n states can be 3-directed with a word of length , improving the previously known upper bound O(2n). Here the best known lower bound is . |
| |
Keywords: | Algorithms Combinatorial problems |
本文献已被 ScienceDirect 等数据库收录! |
|