I/O-Efficient Shortest Path Queries in Geometric Spanners
نویسندگان
چکیده
We present I/O-efficient algorithms to construct planar Steiner spanners for point sets and sets of polygonal obstacles in the plane, and for constructing the “dumbbell” spanner of [6] for point sets in higher dimensions. As important ingredients to our algorithms, we present I/O-efficient algorithms to color the vertices of a graph of bounded degree, answer binary search queries on topology buffer trees, and preprocess a rooted tree for answering prioritized ancestor queries.
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