In this paper we propose an algorithm which, given a directed graph G, finds the minimum directed feedback vertex set (FVS) of G in O∗(1.9977n) time and polynomial space. To the best of our knowledge, this is the first algorithm computing the minimum directed FVS faster than in O(2n). The algorithm is based on the branch-and-prune principle. The minimum directed FVS is obtained through computin...

In this papel; we present eficient parallel algorithms forjinding a minimum weighted connected dominating set, a minimum weighted Steiner tree for a distance-hereditary graph which take O(1og n) time using O(n+m) processors on a CRCW PRAM, where n and m are the number of vertices and edges of a given graph, respectively. We also find a maximum weighted clique of a distance-hereditary graph in O...

In this paper, we present a new strongly polynomial time algorithm for the minimum cost flow problem, based on a refinement of the Edmonds-Karp scaling technique. Our algorithm solves the uncapacitated minimum cost flow problem as a sequence of O(n log n) shortest path problems on networks with n nodes and m arcs and runs in O(n log n (m + n log n)) time. Using a standard transformation, thjis ...

In this paper, we study different variations of minimum width color-spanning annulus problem among a set of points P = {p1, p2, . . . , pn} in IR, where each point is assigned with a color in {1, 2, . . . , k}. We present algorithms for finding a minimum width color-spanning axis parallel square annulus (CSSA), minimum width color spanning axis parallel rectangular annulus (CSRA), and minimum w...

We give improved algorithms for constructing minimum directed and undirected cycle bases in graphs. For general graphs, the new algorithms are Monte Carlo and have running time O(mω), where ω is the exponent of matrix multiplication. The previous best algorithm had running time Õ(m2n). For planar graphs, the new algorithm is deterministic and has running time O(n2). The previous best algorithm ...

We present an O(1.7548) algorithm finding a minimum feedback vertex set in a graph on n vertices.

A conventional feature compensation module for robust automatic speech recognition is usually designed separately from the training of HMM parameters of the recognizer, albeit a maximum likelihood criterion might be used in both designs. In this paper, we present an environment compensated minimum classification error training approach for the joint design of the feature compensation module and...

We describe a deterministic minimum spanning tree algorithm running in time O(m (m; n)), where is a natural inverse of Ackermann's function and m and n are the number of edges and vertices, respectively. This improves upon the O(m (m; n) log (m; n)) bound established by Chazelle in 1997. A similar O(m (m; n))-time algorithm was discovered independently by Chazelle, predating the algorithm prese...

Efficient polynomial time algorithms are well known for the minimum spanning tree problem. However, given an undirected graph with integer edge weights, minimum spanning trees may not be unique. In this article, we present an algorithm that lists all the minimum spanning trees included in the graph. The computational complexity of the algorithm is O(N(mn+ n2 log n)) in time and O(m) in space, w...