Input driven languages are recognized in log n space
Selected papers of the international conference on "foundations of computation theory" on Topics in the theory of computation
Constructing a perfect matching is in random NC
Combinatorica
Matching is as easy as matrix inversion
Combinatorica
Computing algebraic formulas using a constant number of registers
SIAM Journal on Computing
An optimal parallel algorithm for formula evaluation
SIAM Journal on Computing
Journal of Algorithms
Counting quantifiers, successor relations, and logarithmic space
Journal of Computer and System Sciences - special issue on complexity theory
Making computation count: arithmetic circuits in the nineties
ACM SIGACT News
Making Nondeterminism Unambiguous
SIAM Journal on Computing
Uniform constant-depth threshold circuits for division and iterated multiplication
Journal of Computer and System Sciences - Complexity 2001
Efficient Algorithms for Computing Matching and Chromatic Polynominals on Series-Parallel Graphs
ICCI '92 Proceedings of the Fourth International Conference on Computing and Information: Computing and Information
Parity Problems in Planar Graphs
CCC '07 Proceedings of the Twenty-Second Annual IEEE Conference on Computational Complexity
Undirected connectivity in log-space
Journal of the ACM (JACM)
Planar and Grid Graph Reachability Problems
Theory of Computing Systems - Special Issue: Computation and Logic in the Real World; Guest Editors: S. Barry Cooper, Elvira Mayordomo and Andrea Sorbi
The Isomorphism Problem for k-Trees Is Complete for Logspace
MFCS '09 Proceedings of the 34th International Symposium on Mathematical Foundations of Computer Science 2009
Embeddings of k-connected graphs of pathwidth k
Discrete Applied Mathematics - Structural decompositions, width parameters, and graph labelings (DAS 5)
Arithmetizing Classes Around $\textsf{NC}$1 and $\textsf{L}$
Theory of Computing Systems - Special Issue: Theoretical Aspects of Computer Science; Guest Editors: Wolgang Thomas and Pascal Weil
On the expressive power of planar perfect matching and permanents of bounded treewidth matrices
ISAAC'07 Proceedings of the 18th international conference on Algorithms and computation
The space complexity of k-tree isomorphism
ISAAC'07 Proceedings of the 18th international conference on Algorithms and computation
Logspace algorithms for computing shortest and longest paths in series-parallel graphs
FSTTCS'07 Proceedings of the 27th international conference on Foundations of software technology and theoretical computer science
Reachability In K3,3-free graphs and K5-free graphs is in unambiguous log-space
FCT'09 Proceedings of the 17th international conference on Fundamentals of computation theory
Deterministically Isolating a Perfect Matching in Bipartite Planar Graphs
Theory of Computing Systems - Special Title: Symposium on Theoretical Aspects of Computer Science; Guest Editors: Susanne Albers, Pascal Weil
Logspace Versions of the Theorems of Bodlaender and Courcelle
FOCS '10 Proceedings of the 2010 IEEE 51st Annual Symposium on Foundations of Computer Science
On the bipartite unique perfect matching problem
ICALP'06 Proceedings of the 33rd international conference on Automata, Languages and Programming - Volume Part I
Planarity, determinants, permanents, and (unique) matchings
CSR'07 Proceedings of the Second international conference on Computer Science: theory and applications
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Reachability and shortest path problems are NL-complete for general graphs. They are known to be in L for graphs of tree-width 2 (Jakoby and Tantau in Proceedings of FSTTCS'07: The 27th Annual Conference on Foundations of Software Technology and Theoretical Computer Science, pp. 216---227, 2007). In this paper, we improve these bounds for k-trees, where k is a constant. In particular, the main results of our paper are log-space algorithms for reachability in directed k-trees, and for computation of shortest and longest paths in directed acyclic k-trees.Besides the path problems mentioned above, we also consider the problem of deciding whether a k-tree has a perfect matching (decision version), and if so, finding a perfect matching (search version), and prove that these two problems are L-complete. These problems are known to be in P and in RNC for general graphs, and in SPL for planar bipartite graphs, as shown in Datta et al. (Theory Comput. Syst. 47:737---757, 2010).Our results settle the complexity of these problems for the class of k-trees. The results are also applicable for bounded tree-width graphs, when a tree-decomposition is given as input. The technique central to our algorithms is a careful implementation of the divide-and-conquer approach in log-space, along with some ideas from Jakoby and Tantau (Proceedings of FSTTCS'07: The 27th Annual Conference on Foundations of Software Technology and Theoretical Computer Science, pp. 216---227, 2007) and Limaye et al. (Theory Comput. Syst. 46(3):499---522, 2010).