127 search results - page 1 / 26 » The Directed Planar Reachability Problem |
FSTTCS
2005
Springer
13 years 10 months ago
2005
Springer
We investigate the s-t-connectivity problem for directed planar graphs, which is hard for L and is contained in NL but is not known to be complete. We show that this problem is log...
COCO
2007
Springer
13 years 11 months ago
2007
Springer
We make progress in understanding the complexity of the graph reachability problem in the context of unambiguous logarithmic space computation; a restricted form of nondeterminism....
COCO
2010
Springer
13 years 9 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...
FCT
2009
Springer
13 years 9 months ago
2009
Springer
We show that the reachability problem for directed graphs that are either K3,3-free or K5-free is in unambiguous log-space, UL coUL. This significantly extends the result of Bour...
ECCC
2010
13 years 2 months ago
2010
We consider the reachability problem for a certain class of directed acyclic graphs embedded on surfaces. Let G(m, g) be the class of directed acyclic graphs with m = m(n) source ...