English

Heaviest Induced Ancestors and Longest Common Substrings

Data Structures and Algorithms 2013-07-16 v2

Abstract

Suppose we have two trees on the same set of leaves, in which nodes are weighted such that children are heavier than their parents. We say a node from the first tree and a node from the second tree are induced together if they have a common leaf descendant. In this paper we describe data structures that efficiently support the following heaviest-induced-ancestor query: given a node from the first tree and a node from the second tree, find an induced pair of their ancestors with maximum combined weight. Our solutions are based on a geometric interpretation that enables us to find heaviest induced ancestors using range queries. We then show how to use these results to build an LZ-compressed index with which we can quickly find with high probability a longest substring common to the indexed string and a given pattern.

Cite

@article{arxiv.1305.3164,
  title  = {Heaviest Induced Ancestors and Longest Common Substrings},
  author = {Travis Gagie and Paweł Gawrychowski and Yakov Nekrich},
  journal= {arXiv preprint arXiv:1305.3164},
  year   = {2013}
}
R2 v1 2026-06-22T00:16:19.093Z