Linear-time pointer-machine algorithms for least common ancestors, MST verification, and dominators
STOC '98 Proceedings of the thirtieth annual ACM symposium on Theory of computing
A certifying algorithm for the consecutive-ones property
SODA '04 Proceedings of the fifteenth annual ACM-SIAM symposium on Discrete algorithms
Consecutive ones property testing: cut or swap
CiE'11 Proceedings of the 7th conference on Models of computation in context: computability in Europe
Hi-index | 0.89 |
Let V be a finite set of n elements and F={X"1,X"2,...,X"m} a family of m subsets of V. Two sets X"i and X"j of F overlap if X"i@?X"j@A, X"j@?X"i@A, and X"i@?X"j@A. Two sets X,Y@?F are in the same overlap class if there is a series X=X"1,X"2,...,X"k=Y of sets of F in which each X"iX"i"+"1 overlaps. In this note, we focus on efficiently identifying all overlap classes in O(n+@?"i"="1^m|X"i|) time. We thus revisit the clever algorithm of Dahlhaus [E. Dahlhaus, Parallel algorithms for hierarchical clustering and applications to split decomposition and parity graph recognition, J. Algorithms 36 (2) (2000) 205-240] of which we give a clear presentation and that we simplify to make it practical and implementable in its real worst case complexity. An useful variant of Dahlhaus's approach is also explained.