I/O-Optimal Planar Embedding Using Graph Separators

نویسنده

Norbert Zeh

چکیده

We present a new algorithm to test whether a given graph G is planar and to compute a planar embedding Ĝ of G if such an embedding exists. Our algorithm utilizes a fundamentally new approach based on graph separators to obtain such an embedding. The I/O-complexity of our algorithm is O(sort(N)). A simple simulation technique reduces the I/O-complexity of our algorithm to O(perm(N)). We prove a matching lower bound of Ω(perm(N)) I/Os for computing a planar embedding of a given planar graph.

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