A linear time -approximation for the minimum strongly-connected spanning subgraph problem
نویسندگان
چکیده
منابع مشابه
A linear time 5/3-approximation for the minimum strongly-connected spanning subgraph problem
A linear time -approximation algorithm is presented for the NP-hard problem of finding a minimum strongly-connected spanning subgraph. It is based on cycle contraction that was first introduced by Khuller, Raghavachari and Young (1995). We improve their result by contracting special cycles and utilizing a more efficient data structure.
متن کاملA Better Approximation Ratio for the Minimum k-Edge-Connected Spanning Subgraph Problem
Consider the minimum k-edge-connected spanning subgraph problem: given a positive integer k and a k-edge-connected graph G, nd a k-edge-connected spanning subgraph of G with minimum number of edges. This problem is known to be NP-complete. Khuller and Raghavachari presented the rst algorithm with a performance ratio smaller than 2 for all k. They proved an upper bound of 1.85 for the performanc...
متن کاملOn the Minimum Labelling Spanning bi-Connected Subgraph problem
We introduce the minimum labelling spanning bi-connected subgraph problem (MLSBP) replacing connectivity by bi-connectivity in the well known minimum labelling spanning tree problem (MLSTP). A graph is bi-connected if, for every two vertices, there are, at least, two vertex-disjoint paths joining them. The problem consists in finding the spanning bi-connected subgraph or block with minimum set ...
متن کاملLinear-time approximation schemes for planar minimum three-edge connected and three-vertex connected spanning subgraphs
We present the first polynomial-time approximation schemes, i.e., (1 + )-approximation algorithm for any constant > 0, for the minimum three-edge connected spanning subgraph problem and the minimum three-vertex connected spanning subgraph problem in undirected planar graphs. Both the approximation schemes run in linear time. This material is based upon work supported by the National Science Fou...
متن کاملStrongly Connected Spanning Subgraph for Almost Symmetric Networks
In the strongly connected spanning subgraph (SCSS) problem, the goal is to find a minimum weight spanning subgraph of a strongly connected directed graph that maintains the strong connectivity. In this paper, we consider the SCSS problem for two families of geometric directed graphs; t-spanners and symmetric disk graphs. Given a constant t ≥ 1, a directed graph G is a t-spanner of a set of poin...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Information Processing Letters
سال: 2003
ISSN: 0020-0190
DOI: 10.1016/s0020-0190(02)00476-3