A Bounded Path Propagator on Directed Graphs
نویسندگان
چکیده
Path finding is an ubiquitous problem in optimization and graphs in general, for which fast algorithms exist. Yet, in many cases side constraints make these well known algorithms inapplicable. In this paper we study constraints to find shortest paths on a weighted directed graph with arbitrary side constraints. We use the conjunction of two directed tree constraints to model the path, and a bounded path propagator to take into account the weights of the arcs. We show how to implement these constraints with explanations so that we can make use of powerful constraint programming solving techniques using learning. We give experiments to show how the resulting propagators substantially accelerate the solving of complex path problems on directed graphs.
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