Fast algorithms for finding nearest common ancestors
SIAM Journal on Computing
An improved algorithm for transitive closure on acyclic digraphs
Theoretical Computer Science - Thirteenth International Colloquim on Automata, Languages and Programming, Renne
On finding lowest common ancestors: simplification and parallelization
SIAM Journal on Computing
Efficient implementation of lattice operations
ACM Transactions on Programming Languages and Systems (TOPLAS)
Matrix multiplication via arithmetic progressions
Journal of Symbolic Computation - Special issue on computational algebraic complexity
Finding lowest common ancestors in arbitrarily directed trees
Information Processing Letters
New algorithms for the LCA problem and the binary tree reconstruction problem
Information Processing Letters
Finding level-ancestors in trees
Journal of Computer and System Sciences
Rectangular matrix multiplication revisited
Journal of Complexity
Applications of Path Compression on Balanced Trees
Journal of the ACM (JACM)
The lowest common ancestor problem on a tree with an unfixed root
Information Sciences: an International Journal
Finding least common ancestors in directed acyclic graphs
SODA '01 Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms
Characterizing and Mining the Citation Graph of the Computer Science Literature
Knowledge and Information Systems
Dynamic Transitive Closure via Dynamic Matrix Inverse (Extended Abstract)
FOCS '04 Proceedings of the 45th Annual IEEE Symposium on Foundations of Computer Science
SIAM Journal on Computing
Lowest common ancestors in trees and directed acyclic graphs
Journal of Algorithms
LCA queries in directed acyclic graphs
ICALP'05 Proceedings of the 32nd international conference on Automata, Languages and Programming
Acyclic type-of-relationship problems on the internet
CAAN'06 Proceedings of the Third international conference on Combinatorial and Algorithmic Aspects of Networking
All-pairs ancestor problems inweighted dags
ESCAPE'07 Proceedings of the First international conference on Combinatorics, Algorithms, Probabilistic and Experimental Methodologies
All-pairs disjoint paths from a common ancestor in Õ(nω) time
Theoretical Computer Science
A Path Cover Technique for LCAs in Dags
SWAT '08 Proceedings of the 11th Scandinavian workshop on Algorithm Theory
Faster multi-witnesses for Boolean matrix multiplication
Information Processing Letters
New common ancestor problems in trees and directed acyclic graphs
Information Processing Letters
A scalable approach to computing representative lowest common ancestor in directed acyclic graphs
Theoretical Computer Science
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This work studies lowest common ancestor computations in directed acyclic graphs. We present fast algorithms for solving the ALL-PAIRS REPRESENTATIVE LCA and ALL-PAIRS ALL LCA problems with expected running time of O(n2 log n) and O(n3 log log n) respectively, where the expectation is taken over a distribution of input graphs. The speed-ups over recently developed methods are achieved by applying transitive reduction on the input dags. The algorithms are experimentally evaluated against previous approaches demonstrating a significant improvement. On the purely theoretical side, we improve the upper bound for ALL-PAIRS ALL LCA to O(n3.3399). We give first fully dynamic algorithms for both ALL-PAIRS REPRESENTATIVE LCA and ALL-PAIRS ALL LCA. Here, the non-trivial update complexities are O(n2.5) and O(n3) respectively, with constant query times.