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Related papers: Path Contraction Faster than $2^n$

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$H$-Packing is the problem of finding a maximum number of vertex-disjoint copies of $H$ in a given graph $G$. $H$-Partition is the special case of finding a set of vertex-disjoint copies that cover each vertex of $G$ exactly once. Our goal…

Data Structures and Algorithms · Computer Science 2025-09-09 Barış Can Esmer , Dániel Marx

In the spanning tree congestion problem, given a connected graph $G$, the objective is to compute a spanning tree $T$ in $G$ that minimizes its maximum edge congestion, where the congestion of an edge $e$ of $T$ is the number of edges in…

Computational Complexity · Computer Science 2023-07-12 Huong Luu , Marek Chrobak

In the decremental single-source shortest paths (SSSP) problem we want to maintain the distances between a given source node $s$ and every other node in an $n$-node $m$-edge graph $G$ undergoing edge deletions. While its static counterpart…

Data Structures and Algorithms · Computer Science 2018-08-20 Monika Henzinger , Sebastian Krinninger , Danupon Nanongkai

In the unsplittable flow problem on a path, we are given a capacitated path $P$ and $n$ tasks, each task having a demand, a profit, and start and end vertices. The goal is to compute a maximum profit set of tasks, such that for each edge…

Data Structures and Algorithms · Computer Science 2015-03-19 Paul Bonsma , Jens Schulz , Andreas Wiese

Vertex deletion and edge deletion problems play a central role in Parameterized Complexity. Examples include classical problems like Feedback Vertex Set, Odd Cycle Transversal, and Chordal Deletion. Interestingly, the study of edge…

Data Structures and Algorithms · Computer Science 2011-04-20 Pinar Heggernes , Pim van 't Hof , Benjamin Lévêque , Daniel Lokshtanov , Christophe Paul

Let G be a directed graph with n vertices and non-negative weights in its directed edges, embedded on a surface of genus g, and let f be an arbitrary face of G. We describe a randomized algorithm to preprocess the graph in O(gn log n) time…

Data Structures and Algorithms · Computer Science 2013-05-13 Sergio Cabello , Erin Wolf Chambers , Jeff Erickson

A signed tree model of a graph $G$ is a compact binary structure consisting of a rooted binary tree whose leaves are bijectively mapped to the vertices of $G$, together with 2-colored edges $xy$, called transversal pairs, interpreted as…

Data Structures and Algorithms · Computer Science 2026-02-19 Édouard Bonnet , Colin Geniet , Eun Jung Kim , Sungmin Moon

The single-source shortest path problem is a classical problem in the research field of graph algorithm. In this paper, a new single-source shortest path algorithm for nonnegative weight graph is proposed. The algorithm can compress…

Data Structures and Algorithms · Computer Science 2015-10-16 Yunpeng Li

A graph $G = (V,E)$ is $\textit{monopolar}$ if its vertex set admits a partition $V = (C \uplus{} I)$ where $G[C]$ is a $\textit{cluster graph}$ and $I$ is an $\textit{independent set}$ in $G$; this is a \textit{monopolar partition} of $G$.…

Data Structures and Algorithms · Computer Science 2025-07-08 Geevarghese Philip , Shrinidhi Teganahally Sridhara

We give an algorithm that, given graphs $G$ and $H$, tests whether $H$ is a minor of $G$ in time ${\cal O}_H(n^{1+o(1)})$; here, $n$ is the number of vertices of $G$ and the ${\cal O}_H(\cdot)$-notation hides factors that depend on $H$ and…

Data Structures and Algorithms · Computer Science 2024-04-08 Tuukka Korhonen , Michał Pilipczuk , Giannos Stamoulis

We present a randomized algorithm for the single-source shortest paths (SSSP) problem on directed graphs with arbitrary real-valued edge weights that runs in $n^{2+o(1)}$ time with high probability. This result yields the first almost…

Data Structures and Algorithms · Computer Science 2026-02-19 Sanjeev Khanna , Junkai Song

We study the problem of computing shortest paths in so-called dense distance graphs. Every planar graph $G$ on $n$ vertices can be partitioned into a set of $O(n/r)$ edge-disjoint regions (called an $r$-division) with $O(r)$ vertices each,…

Data Structures and Algorithms · Computer Science 2016-07-18 Paweł Gawrychowski , Adam Karczmarz

In the Disjoint Shortest Paths problem one is given a graph $G$ and a set $\mathcal{T}=\{(s_1,t_1),\dots,(s_k,t_k)\}$ of $k$ vertex pairs. The question is whether there exist vertex-disjoint paths $P_1,\dots,P_k$ in $G$ so that each $P_i$…

Data Structures and Algorithms · Computer Science 2025-05-07 Michał Pilipczuk , Giannos Stamoulis , Michał Włodarczyk

We prove a robust contraction decomposition theorem for $H$-minor-free graphs, which states that given an $H$-minor-free graph $G$ and an integer $p$, one can partition in polynomial time the vertices of $G$ into $p$ sets $Z_1,\dots,Z_p$…

Data Structures and Algorithms · Computer Science 2024-12-06 Sayan Bandyapadhyay , William Lochet , Daniel Lokshtanov , Dániel Marx , Pranabendu Misra , Daniel Neuen , Saket Saurabh , Prafullkumar Tale , Jie Xue

Given a graph $G$, we define ${\bf bcg}(G)$ as the minimum $k$ for which $G$ can be contracted to the uniformly triangulated grid $\Gamma_{k}$. A graph class ${\cal G}$ has the SQG${\bf C}$ property if every graph $G\in{\cal G}$ has…

Combinatorics · Mathematics 2022-07-21 Julien Baste , Dimitrios M. Thilikos

We present improved deterministic algorithms for approximating shortest paths in the Congested Clique model of distributed computing. We obtain $poly(\log\log n)$-round algorithms for the following problems in unweighted undirected…

Data Structures and Algorithms · Computer Science 2020-03-09 Michal Dory , Merav Parter

Given a graph $G$ cellularly embedded on a surface $\Sigma$ of genus $g$, a cut graph is a subgraph of $G$ such that cutting $\Sigma$ along $G$ yields a topological disk. We provide a fixed parameter tractable approximation scheme for the…

Data Structures and Algorithms · Computer Science 2015-07-08 Vincent Cohen-Addad , Arnaud de Mesmay

In the k-Disjoint Shortest Paths problem, a set of terminal pairs of vertices $\{(s_i,t_i)\mid 1\le i\le k\}$ is given and we are asked to find paths $P_1,\ldots,P_k$ such that each path $P_i$ is a shortest path from $s_i$ to $t_i$ and…

Data Structures and Algorithms · Computer Science 2021-07-08 Saeed Akhoondian Amiri , Julian Wargalla

An ordered graph is a graph enhanced with a linear order on the vertex set. An ordered graph is a core if it does not have an order-preserving homomorphism to a proper subgraph. We say that $H$ is the core of $G$ if (i) $H$ is a core, (ii)…

Computational Complexity · Computer Science 2025-12-01 Michal Čertík , Andreas Emil Feldmann , Jaroslav Nešetřil , Paweł Rzążewski

The Subgraph Isomorphism problem asks, given a host graph G on n vertices and a pattern graph P on k vertices, whether G contains a subgraph isomorphic to P. The restriction of this problem to planar graphs has often been considered. After…

Discrete Mathematics · Computer Science 2015-03-19 Paul Bonsma