Intersection Non-Emptiness for Tree Shaped Finite Automata
نویسنده
چکیده
In recent work on the Clique problem by Chen, Huang, Kanj, and Xia (2006) it was shown that if k-Clique is solvable in no(k) time, then the exponential time hypothesis is false. In this work, we focus on a related parameterized problem called intersection non-emptiness. We show that if intersection non-emptiness for two tree shaped DFA’s is solvable in O(n2− ) time, then the strong exponential time hypothesis is false. Further, we show that if intersection non-emptiness for k tree shaped DFA’s is solvable in no(k) time, then the exponential time hypothesis is false. 1998 ACM Subject Classification F.1.1 Models of Computation, F1.3 Complexity Measures and Classes, F.4.3 Formal Languages
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