59 search results - page 2 / 12 » Lattice Structures from Planar Graphs |
ESA
2007
Springer
13 years 11 months ago
2007
Springer
We present an experimental evaluation of an approximate distance oracle recently suggested by Thorup [1] for undirected planar graphs. The oracle uses the existence of graph separa...
COCO
2010
Springer
13 years 8 months ago
2010
Springer
Designing algorithms that use logarithmic space for graph reachability problems is fundamental to complexity theory. It is well known that for general directed graphs this problem...
COMPGEOM
2010
ACM
13 years 10 months ago
2010
ACM
A graph is near-planar if it can be obtained from a planar graph by adding an edge. We show that it is NP-hard to compute the crossing number of near-planar graphs. The main idea ...
STACS
2009
Springer
13 years 11 months ago
2009
Springer
We present the first polynomial-time approximation schemes (PTASes) for the following subset-connectivity problems in edge-weighted graphs of bounded genus: Steiner tree, low-conn...
ICALP
2009
Springer
14 years 5 months ago
2009
Springer
We develop new structural results for apex-minor-free graphs and show their power by developing two new approximation algorithms. The first is an additive approximation for colorin...