Fast Exponential-Time Algorithms for the Forest Counting in Graph Classes
نویسندگان
چکیده
We prove #P-completeness for counting the number of forests in regular graphs and chordal graphs. We also present algorithms for this problem, running in O∗(1.8494m) time for 3-regular graphs, and O∗(1.9706m) time for unit interval graphs, where m is the number of edges in the graph and O∗-notation ignores a polynomial factor. The algorithms can be generalized to the Tutte polynomial computation.
منابع مشابه
Fast Exponential-Time Algorithms for the Forest Counting and the Tutte Polynomial Computation in Graph Classes
We prove #P-completeness for counting the number of forests in regular graphs and chordal graphs. We also present algorithms for this problem, running in O∗(1.8494m) time for 3-regular graphs, and O∗(1.9706m) time for unit interval graphs, where m is the number of edges in the graph and O∗-notation ignores a polynomial factor. The algorithms can be generalized to the Tutte polynomial computation.
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