On Graphs with Characteristic Bounded-Width Functions
نویسنده
چکیده
Graphs can be represented symbolically by the Ordered Binary Decision Diagram (OBDD) of their characteristic Boolean function. The latter is said to have bounded width b if its minimal-size complete OBDD has bounded width b. Bounded-width functions have small OBDDs and allow efficient functional operations. Therefore, they are of interest in the analysis of symbolic graph algorithms. In this paper, a variety of graph sequences is proved to have characteristic functions of bounded-width. It is shown that this property is closed under important graph composition operations. Finally, an unpleasant property of a naive symbolic all-pairs shortest-paths algorithm in the context of bounded-width functions is presented.
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