Vertex cover

Bài giảng chương 8 trang bị cho người học những hiểu biết về thuật toán xấp xỉ. Trong chương này người học có thể tìm hiểu một số bài toán phủ đỉnh và một số vấn đề về phủ đỉnh. Mời các bạn cùng tham khảo để nắm bắt các nội dung chi tiết.

22p youcanletgo_01 04-01-2016 90 8   Download

We prove the Minimum Vertex Cover problem to be NP-hard to approximate to within a factor of 1.3606, extending on previous PCP and hardness of approximation technique. To that end, one needs to develop a new proof framework, and to borrow and extend ideas from several fields. 1. Introduction The basic purpose of computational complexity theory is to classify computational problems according to the amount of resources required to solve them. In particular, the most basic task is to classify computational problems to those that are efficiently solvable and those that are not. ...

48p noel_noel 17-01-2013 60 6   Download

Let G be a graph with vertex set V (G) = {1, . . . , n} and edge set E(G). We are interested in studying the functions of the graph G whose values belong to the interval [(G), (G)]. Here (G) is the size of the largest stable set in G and (G) is the smallest number of cliques that cover the vertices of G. It is well known (see, for example, [1]) that for some  0 it is impossible to approximate in polynomial time (G) and (G) within a factor of n, assuming P 6= NP. We suppose that better approximation could...

5p thulanh5 12-09-2011 66 4   Download