The Complexity of Maximum Matroid-Greedoid Intersection
نویسندگان
چکیده
The maximum intersection problem for a matroid and a greedoid, given by polynomial-time oracles, is shown NP -hard by expressing the satisfiability of boolean formulas in 3-conjunctive normal form as such an intersection. Also the corresponding approximation problem is shown NP -hard for certain approximation performance bounds. This is in contrast with the maximum matroid-matroid intersection which is solvable in polynomial time by an old result of Edmonds.
منابع مشابه
The Complexity of Maximum Matroid-Greedoid Intersection and Weighted Greedoid Maximization
The maximum intersection problem for a matroid and a greedoid, given by polynomial-time oracles, is shown NP -hard by expressing the satis ability of boolean formulas in 3-conjunctive normal form as such an intersection. The corresponding approximation problems are shown NP -hard for certain approximation performance bounds. Moreover, some natural parameterized variants of the problem are shown...
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