English
Related papers

Related papers: Cops and Attacking Robbers with Cycle Constraints

200 papers

A (finite or infinite) graph is called constructible if it may be obtained recursively from the one-point graph by repeatedly adding dominated vertices. In the finite case, the constructible graphs are precisely the cop-win graphs, but for…

Combinatorics · Mathematics 2022-08-02 Maria-Romina Ivan , Imre Leader , Mark Walters

"Zombies and Survivor" is a variant of the well-studied game of "Cops and Robber" where the zombies (cops) can only move closer to the survivor (robber). We consider the deterministic version of the game where a zombie can choose their path…

Combinatorics · Mathematics 2021-06-04 Valentin Bartier , Laurine Bénéteau , Marthe Bonamy , Hoang La , Jonathan Narboni

We propose a definition of generalized Cops and Robbers games where there are two players, the Pursuer and the Evader, who each move via prescribed rules. If the Pursuer can ensure that the game enters into a fixed set of final positions,…

Combinatorics · Mathematics 2017-04-20 Anthony Bonato , Gary MacGillivray

We consider a variation of Cops and Robber, introduced in [D. Cox and A. Sanaei, The damage number of a graph, [Aust. J. of Comb. 75(1) (2019) 1-16] where vertices visited by a robber are considered damaged and a single cop aims to minimize…

Combinatorics · Mathematics 2024-12-19 Melissa A. Huggan , Margaret-Ellen Messinger , Amanda Porter

In previous work, we introduced median decompositions, a generalisation of tree decompositions where a graph can be modelled after any median graph, along with a hierarchy of $i$-medianwidth parameters $(mw_i)_{i\geq 1}$ starting from…

Combinatorics · Mathematics 2016-03-23 Konstantinos Stavropoulos

The cops-and-robber (CR) game has been used in mobile robotics as a discretized model (played on a graph G) of pursuit/evasion problems. The "classic" CR version is a perfect information game: the cops' (pursuer's) location is always known…

Discrete Mathematics · Computer Science 2014-02-26 Athanasios Kehagias , Dieter Mitsche , Pawel Pralat

We study the game of Cops and Robbers, where cops try to capture a robber on the vertices of a graph. Meyniel's conjecture states that for every connected graph $G$ on $n$ vertices, the cop number of $G$ is upper bounded by $O(\sqrt{n})$,…

Combinatorics · Mathematics 2019-09-09 Fatemeh Hasiri , Igor Shinkar

We study relations between diameter $D(G)$, domination number $\gamma(G)$, independence number $\alpha(G)$ and cop number $c(G)$ of a connected graph $G$, showing (i.) $c(G) \leq \alpha(G)-\lfloor \frac{D(G)-3}{2} \rfloor$, and (ii.) $c(G)…

Combinatorics · Mathematics 2023-03-21 Jan Petr , Julien Portier , Leo Versteegen

The recently introduced variation of the game of cops and robber is played on geodesic spaces. In this paper we establish some general strategies for the players, in particular the generalized radial strategy and the covering space…

Metric Geometry · Mathematics 2022-11-07 Vesna Iršič , Bojan Mohar , Alexandra Wesolek

We consider a search and rescue game introduced recently by the first author. An immobile target or targets (for example, injured hikers) are hidden on a graph. The terrain is assumed to dangerous, so that when any given vertex of the graph…

Data Structures and Algorithms · Computer Science 2023-04-10 Thomas Lidbetter , Yifan Xie

Meyniel's conjecture states that $n$-vertex connected graphs have cop number $O(\sqrt{n})$. The current best known upper bound is $n/2^{(1-o(1))\sqrt{\log n}}$, proved independently by Lu and Peng (2011), and by Scott and Sudakov (2011). In…

Combinatorics · Mathematics 2026-02-10 Prosenjit Bose , Louis Esperet , Jędrzej Hodor , Gwenaël Joret , Piotr Micek , Clément Rambaud

We consider a new probabilistic graph searching game played on graphs, inspired by the familiar game of Cops and Robbers. In Zombies and Survivors, a set of zombies attempts to eat a lone survivor loose on a given graph. The zombies…

Discrete Mathematics · Computer Science 2015-03-31 Anthony Bonato , Dieter Mitsche , Xavier Pérez-Giménez , Paweł Prałat

We introduce the bodyguard problem for graphs. This is a variation of Surrounding Cops and Robber but, in this model, a smallest possible group of bodyguards must surround the president and then maintain this protection indefinitely. We…

Combinatorics · Mathematics 2025-08-15 Nancy E. Clarke , Danny Dyer , William Kellough

A cop tries to capture a robber in a topological space $X$ being unable to see him. For which spaces $X$ does the cop have a strategy which allows him to capture the robber independently of his efforts to escape? In other words, when is…

General Topology · Mathematics 2022-10-24 Jonathan A. Barmak

We define the cover number of a graph $G$ by a graph class $\mathcal P$ as the minimum number of graphs of class $\mathcal P$ required to cover the edge set of $G$. Taking inspiration from a paper by Harary, Hsu and Miller, we find an exact…

Combinatorics · Mathematics 2025-02-24 Márton Marits

We bound expected capture time and throttling number for the cop versus gambler game on a connected graph with $n$ vertices, a variant of the cop versus robber game that is played in darkness, where the adversary hops between vertices using…

Discrete Mathematics · Computer Science 2019-06-03 Jesse Geneson , Carl Joshua Quines , Espen Slettnes , Shen-Fu Tsai

The graph grabbing game is played on a non-negatively weighted connected graph by Alice and Bob who alternately claim a non-cut vertex from the remaining graph, where Alice plays first, to maximize the weights on their respective claimed…

Combinatorics · Mathematics 2020-07-24 Sopon Boriboon , Teeradej Kittipassorn

A team of $r$ {\it revolutionaries} and a team of $s$ {\it spies} play a game on a graph $G$. Initially, revolutionaries and then spies take positions at vertices. In each subsequent round, each revolutionary may move to an adjacent vertex…

Combinatorics · Mathematics 2015-08-06 Daniel W. Cranston , Clifford D. Smyth , Douglas B. West

We consider the localization game played on graphs in which a cop tries to determine the exact location of an invisible robber by exploiting distance probes. The corresponding graph parameter $\zeta(G)$ for a given graph $G$ is called the…

Combinatorics · Mathematics 2020-09-07 Andrzej Dudek , Sean English , Alan Frieze , Calum MacRury , Pawel Pralat

Cop-width and flip-width are new families of graph parameters introduced by Toru\'nczyk (2023) that generalise treewidth, degeneracy, generalised colouring numbers, clique-width and twin-width. In this paper, we bound the cop-width and…

Combinatorics · Mathematics 2025-05-14 Robert Hickingbotham