Analysis of a High-Performance TSP Solver on the GPU
Graphical Processing Units have been applied to solve NP-hard problems with no known polynomial time solutions. An example of such a problem is the Traveling Salesman Problem (TSP). The TSP is one of the most commonly studied combinatorial optimization ...
Graph Bisection with Pareto Optimization
We introduce FlowCutter, a novel algorithm to compute a set of edge cuts or node separators that optimize cut size and balance in the Pareto sense. Our core algorithm heuristically solves the balanced connected st-edge-cut problem, where two given nodes ...
Complexity of Coloring Random Graphs: An Experimental Study of the Hardest Region
It is known that the problem of deciding k-colorability of a graph exhibits an easy-hard-easy pattern,—that is, the average-case complexity for backtrack-type algorithms, as a function of k, has a peak. This complexity peak is either at k = χ − 1 or k = ...
Dynamic Merging of Frontiers for Accelerating the Evaluation of Betweenness Centrality
Betweenness Centrality (BC) is a widely used metric of the relevance of a node in a network. The fastest-known algorithm for the evaluation of BC on unweighted graphs builds a tree representing information about the shortest paths for each vertex to ...
Improving the Betweenness Centrality of a Node by Adding Links
- Elisabetta Bergamini,
- Pierluigi Crescenzi,
- Gianlorenzo D'angelo,
- Henning Meyerhenke,
- Lorenzo Severini,
- Yllka Velaj
Betweenness is a well-known centrality measure that ranks the nodes according to their participation in the shortest paths of a network. In several scenarios, having a high betweenness can have a positive impact on the node itself. Hence, in this ...
Updating Dynamic Random Hyperbolic Graphs in Sublinear Time
Generative network models play an important role in algorithm development, scaling studies, network analysis, and realistic system benchmarks for graph data sets. A complex network model gaining considerable popularity builds random hyperbolic graphs, ...
Connection Scan Algorithm
We introduce the Connection Scan Algorithm (CSA) to efficiently answer queries to timetable information systems. The input consists, in the simplest setting, of a source position and a desired target position. The output consists of a sequence of ...
Practical Minimum Cut Algorithms
The minimum cut problem for an undirected edge-weighted graph asks us to divide its set of nodes into two blocks while minimizing the weight sum of the cut edges. Here, we introduce a linear-time algorithm to compute near-minimum cuts. Our algorithm is ...
Constructing a High-Dimensional kNN-Graph Using a Z-Order Curve
Although many fast methods exist for constructing a kNN-graph for low-dimensional data, it is still an open question how to do it efficiently for high-dimensional data. We present a new method to construct an approximate kNN-graph for medium- to high-...
Computing Critical Nodes in Directed Graphs
We consider the critical node detection problem (CNDP) in directed graphs, which can be defined as follows. Given a directed graph G and a parameter k, we wish to remove a subset S of at most k vertices of G such that the residual graph G∖S has minimum ...
An Efficient Algorithm for the 1D Total Visibility-Index Problem and Its Parallelization
- Peyman Afshani,
- Mark De Berg,
- Henri Casanova,
- Ben Karsin,
- Colin Lambrechts,
- Nodari Sitchinava,
- Constantinos Tsirogiannis
Let T be a terrain and P be a set of points on its surface. An important problem in Geographic Information Science (GIS) is computing the visibility index of a point p on P, that is, the number of points in P that are visible from p. The total ...
Computing the Expected Value and Variance of Geometric Measures
Let P be a point set in ℝd, and let M be a function that maps any subset of P to a positive real. We examine the problem of computing the mean and variance of M when a subset in P is selected according to a random distribution. We consider two ...
I/O-Efficient Generation of Massive Graphs Following the LFR Benchmark
LFR is a popular benchmark graph generator used to evaluate community detection algorithms. We present EM-LFR, the first external memory algorithm able to generate massive complex networks following the LFR benchmark. Its most expensive component is the ...
