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In this paper we show that two-dimensional nearest neighbor queries can be answered in optimal $O(\log n)$ time while supporting insertions in $O(\log^{1+\varepsilon}n)$ time. No previous data structure was known that supports $O(\log…

Data Structures and Algorithms · Computer Science 2025-04-11 John Iacono , Yakov Nekrich

We introduce an improved structure of distance sensitivity oracle (DSO). The task is to pre-process a non-negatively weighted graph so that a data structure can quickly answer replacement path length for every triple of source, terminal and…

Data Structures and Algorithms · Computer Science 2016-05-17 Ran Duan , Tianyi Zhang

Consider a forest that evolves via $link$ operations that make the root of one tree the child of a node in another tree. Intermixed with $link$ operations are $nca$ operations, which return the nearest common ancestor of two given nodes…

Data Structures and Algorithms · Computer Science 2016-11-23 Harold N. Gabow

Navarro and Sadakane [TALG 2014] gave a dynamic succinct data structure for storing an ordinal tree. The structure supports tree queries in either $O(\log n/\log\log n)$ or $O(\log n)$ time, and insertion or deletion of a single node in…

Data Structures and Algorithms · Computer Science 2018-05-30 Dekel Tsur

The treedepth of a graph $G$ is the least possible depth of an elimination forest of $G$: a rooted forest on the same vertex set where every pair of vertices adjacent in $G$ is bound by the ancestor/descendant relation. We propose an…

Data Structures and Algorithms · Computer Science 2022-05-06 Wojciech Nadara , Michał Pilipczuk , Marcin Smulewicz

We solve the dynamic Predecessor Problem with high probability (whp) in constant time, using only $n^{1+\delta}$ bits of memory, for any constant $\delta > 0$. The input keys are random wrt a wider class of the well studied and practically…

Data Structures and Algorithms · Computer Science 2011-04-25 D. Belazzougui , A. C. Kaporis , P. G. Spirakis

We consider a multi-level aggregation problem in a weighted rooted tree, studied recently by Bienkowski et al. (2015). In this problem requests arrive over time at the nodes of the tree, and each request specifies a deadline. A request is…

Data Structures and Algorithms · Computer Science 2017-01-10 Niv Buchbinder , Moran Feldman , Joseph Naor , Ohad Talmon

We design a space-efficient algorithm for performing depth-first search traversal(DFS) of a graph in $O(m+n\log^* n)$ time using $O(n)$ bits of space. While a normal DFS algorithm results in a DFS-tree (in case the graph is connected), our…

Data Structures and Algorithms · Computer Science 2018-10-18 Jayesh Choudhari , Manoj Gupta , Shivdutt Sharma

We revisit the Heaviest Induced Ancestors (HIA) problem that was introduced by Gagie, Gawrychowski, and Nekrich [CCCG 2013] and has a number of applications in string algorithms. Let $T_1$ and $T_2$ be two rooted trees whose nodes have…

Data Structures and Algorithms · Computer Science 2023-02-06 Panagiotis Charalampopoulos , Bartłomiej Dudek , Paweł Gawrychowski , Karol Pokorski

For k>=1, we consider the graph dynamical system known as a k-reversible process. In such process, each vertex in the graph has one of two possible states at each discrete time. Each vertex changes its state between the present time and the…

Data Structures and Algorithms · Computer Science 2014-12-01 Leonardo I. L. Oliveira , Valmir C. Barbosa , Fábio Protti

We describe a framework for maintaining forest algebra representations that are of logarithmic height for unranked trees. Such representations can be computed in O(n) time and updated in O(log(n)) time. The framework is of potential…

Logic in Computer Science · Computer Science 2025-10-08 Sarah Kleest-Meißner , Jonas Marasus , Matthias Niewerth

We consider online algorithms for the $k$-server problem on trees. There is a $k$-competitive algorithm for this problem, and it is the best competitive ratio. M. Chrobak and L. Larmore provided it. At the same time, the existing…

Data Structures and Algorithms · Computer Science 2022-05-02 Kamil Khadiev , Maxim Yagafarov

Given two rooted, ordered, and labeled trees $P$ and $T$ the tree inclusion problem is to determine if $P$ can be obtained from $T$ by deleting nodes in $T$. This problem has recently been recognized as an important query primitive in XML…

Data Structures and Algorithms · Computer Science 2011-01-19 Philip Bille , Inge Li Goertz

We present space-efficient parallel strategies for two fundamental combinatorial search problems, namely, backtrack search and branch-and-bound, both involving the visit of an $n$-node tree of height $h$ under the assumption that a node can…

Data Structures and Algorithms · Computer Science 2014-03-27 Andrea Pietracaprina , Geppino Pucci , Francesco Silvestri , Fabio Vandin

The most successful unfolding rules used nowadays in the partial evaluation of logic programs are based on well quasi orders (wqo) applied over (covering) ancestors, i.e., a subsequence of the atoms selected during a derivation. Ancestor…

Programming Languages · Computer Science 2009-11-23 G. Puebla , E. Albert , M. Hermenegildo

Understanding how the time-complexity of evolutionary algorithms (EAs) depend on their parameter settings and characteristics of fitness landscapes is a fundamental problem in evolutionary computation. Most rigorous results were derived…

Neural and Evolutionary Computing · Computer Science 2016-10-28 Dogan Corus , Duc-Cuong Dang , Anton V. Eremeev , Per Kristian Lehre

In this paper, we revisit the much studied LCS problem for two given sequences. Based on the algorithm of Iliopoulos and Rahman for solving the LCS problem, we have suggested 3 new improved algorithms. We first reformulate the problem in a…

Data Structures and Algorithms · Computer Science 2015-08-25 Daxin Zhu , Lei Wang , Yingjie Wu , Xiaodong Wang

Approximate nearest-neighbor search is a fundamental algorithmic problem that continues to inspire study due its essential role in numerous contexts. In contrast to most prior work, which has focused on point sets, we consider…

Computational Geometry · Computer Science 2021-04-01 Ahmed Abdelkader , David M. Mount

For a static array A of n ordered objects, a range minimum query asks for the position of the minimum between two specified array indices. We show how to preprocess A into a scheme of size 2n+o(n) bits that allows to answer range minimum…

Data Structures and Algorithms · Computer Science 2009-12-02 Johannes Fischer

In this paper, we consider the minimum spanning tree problem (for short, MSTP) on an arbitrary set of $n$ points of $d$-dimensional space in $l_1$-norm. For this problem, for each fixed $d\geq 2$, there is a known algorithm of the…

Discrete Mathematics · Computer Science 2024-12-12 K. V. Kaymakov , D. S. Malyshev