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Related papers: Simultaneously Moving Cops and Robbers

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Introduced by Harris, Insko, Prieto Langarica, Stoisavljevic, and Sullivan, the \emph{tipsy cop and drunken robber} is a variant of the cop and robber game on graphs in which the robber simply moves randomly along the graph, while the cop…

Probability · Mathematics 2024-03-13 Pamela E. Harris , Erik Insko , Florian Lehner

In the cops and robber games played on a simple graph $G$, Aigner and Fromme's lemma states that one cop can guard a shortest path in the sense that the robber cannot enter this path without getting caught after finitely many steps. In this…

Combinatorics · Mathematics 2018-04-11 Linyuan Lu , Zhiyu Wang

The deduction game is a variation of the game of cops and robber on graphs in which searchers must capture an invisible evader in at most one move. Searchers know each others' initial locations, but can only communicate if they are on the…

Combinatorics · Mathematics 2024-12-24 Andrea Burgess , Danny Dyer , Mozhgan Farahani

"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

In this note, we prove that all cop-win graphs G in the game in which the robber and the cop move at different speeds s and s' with s'<s, are \delta-hyperbolic with \delta=O(s^2). We also show that the dependency between \delta and s is…

Combinatorics · Mathematics 2018-12-12 Jérémie Chalopin , Victor Chepoi , Panos Papasoglu , Timothée Pecatte

We show that the cop number of every generalized Petersen graph is at most 4. The strategy is to play a modified game of cops and robbers on an infinite cyclic covering space where the objective is to capture the robber or force the robber…

We study the computational complexity of a perfect-information two-player game proposed by Aigner and Fromme. The game takes place on an undirected graph where n simultaneously moving cops attempt to capture a single robber, all moving at…

Computational Complexity · Computer Science 2012-12-19 Marcello Mamino

We explore a variant of the game of Cops and Robber introduced by Bonato et al.~where the robber is invisible unless outside the common neighbourhood of the cops. The hyperopic cop number is analogous to the cop number and we investigate…

Combinatorics · Mathematics 2021-07-16 Nancy E. Clarke , Stephen Finbow , Margaret-Ellen Messinger , Amanda Porter

The game of Cops and Robbers is a well known pursuit-evasion game played on graphs. It has been proved \cite{bounded_degree} that cubic graphs can have arbitrarily large cop number $c(G)$, but the known constructions show only that the set…

The cop number of a graph $G$ is the smallest $k$ such that $k$ cops win the game of cops and robber on $G$. We investigate the maximum cop number of geometric intersection graphs, which are graphs whose vertices are represented by…

In this paper we study the two-player generalized Cops and Robber (GCR) games introduced by Bonato and MacGillivray. Our main goal is to present a full, self-contained game theoretic analysis of such games.

Combinatorics · Mathematics 2020-11-20 Athanasios Kehagias , Georgios Konstantinidis

Interdicting a criminal with limited police resources is a challenging task as the criminal changes location over time. The size of the large transportation network further adds to the difficulty of this scenario. To tackle this issue, we…

Artificial Intelligence · Computer Science 2026-04-08 Sukanya Samanta , Kei Kimura , Makoto Yokoo , Palash Dey

We consider the game of Cops and Robber played on the Cartesian product of two trees. Assuming the players play perfectly, it is shown that if there are two cops in the game, then the length of the game (known as the 2-capture time of the…

Combinatorics · Mathematics 2010-11-02 Abbas Mehrabian

We consider a variant of the Cops and Robbers game where the robber can move t edges at a time, and show that in this variant, the cop number of a d-regular graph with girth larger than 2t+2 is Omega(d^t). By the known upper bounds on the…

Combinatorics · Mathematics 2011-06-03 Abbas Mehrabian

We consider a cops and robber game where the cops are blocking edges of a graph, while the robber occupies its vertices. At each round of the game, the cops choose some set of edges to block and right after the robber is obliged to move to…

Discrete Mathematics · Computer Science 2020-09-09 Stratis Limnios , Christophe Paul , Joanny Perret , Dimitrios M. Thilikos

We consider a variation of a cops and robbers game in which the cop---here referred to as "hunter"---is not constrained by the graph but must play in the dark against a "mole." We characterize the graphs---which we will call…

Combinatorics · Mathematics 2014-05-15 Natasha Komarov , Peter Winkler

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 introduce a new game played on graphs, ``Agents and Adversary". This game is reminiscent of ``Cops and Robbers" but has some fundamental differences. We classify infinite families of graphs as Agents-win and Adversary-win. We then define…

Combinatorics · Mathematics 2026-03-13 William K. Moses , Amanda Redlich , Frederick Stock

We consider a surrounding variant of cops and robbers on graphs of bounded genus. We obtain bounds on the number of cops required to surround a robber on planar graphs, toroidal graphs, and outerplanar graphs. We also obtain improved bounds…

Combinatorics · Mathematics 2019-11-05 Peter Bradshaw , Seyyed Aliasghar Hosseini

The game of cops and robber has been studied for many years. Denoting $\mathsf{Forb}(4K_1)$ to be the family of all graphs that contain no induced subgraph isomorphic to $4K_1$ (e.g., with independence number less than $4$), we prove that…

Combinatorics · Mathematics 2026-01-15 Zhaoyu Wu