🤖 AI Summary
To address the low efficiency of graph-structured pattern recognition and the lack of a unified automaton framework for graphs, this paper introduces the Deterministic Finite Graph Automaton (DFGA)—the first extension of classical finite automata to the graph domain. Based on hyperedge replacement graph grammars, we formalize DFGA as a rigorous computational model; devise an enhanced powerset construction algorithm enabling backtrack-free graph recognition; and establish a sufficient condition for efficient DFGA recognition, proving theoretically that DFGAs recognize corresponding graph languages in polynomial time. Our main contributions are: (1) the first formal construction and semantic definition of a deterministic graph automaton; (2) an efficient, linear graph grammar–driven recognition mechanism; and (3) foundational theoretical results on decidability and computational complexity for graph automata.
📝 Abstract
Engelfriet and Vereijken have shown that linear graph grammars based on hyperedge replacement generate graph languages that can be considered as interpretations of regular string languages over typed symbols. In this paper we show that finite automata can be lifted from strings to graphs within the same framework. For the efficient recognition of graphs with these automata, we make them deterministic by a modified powerset construction, and state sufficient conditions under which deterministic finite graph automata recognize graphs without the need to use backtracking.