Weighted Expressions and DFS Tree Automata
نویسندگان
چکیده
We introduce weighted expressions, a calculus to express quantitative properties over unranked trees. They involve products and sums from a semiring as well as classical boolean formulas. We show that weighted expressions are expressively equivalent to a new class of weighted tree-walking automata. This new automata model is equipped with pebbles, and follows a depthfirst-search policy in the tree.
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تاریخ انتشار 2011