Tree Indexing by Pushdown Automata and Repeats of Subtrees
نویسندگان
چکیده
We consider the problem of finding all subtree repeats in a given unranked ordered tree. We show a new, elegant, and simple method, which is based on the construction of a tree indexing structure called the subtree pushdown automaton. We propose a solution for computing all subtree repeats from the deterministic subtree pushdown automaton constructed over the subject tree. The method we present is directly analogous to the relationship between string deterministic suffix automata and factor repeats in a given string.
منابع مشابه
String Suffix Automata and Subtree Pushdown Automata
String suffix automata accept all suffixes of a given string and belong to the fundamental stringology principles. Extending their transitions by specific pushdown operations results in new subtree pushdown automata, which accept all subtrees of a given subject tree in prefix notation and are analogous to the suffix automata in their properties. The deterministic subtree pushdown automaton acce...
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