Brief Announcement: Cooperative Guarding in Polygons with Holes

Authors John Augustine , Srikkanth Ramachandran

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Author Details

John Augustine
  • Department of Computer Science & Engineering, Indian Institute of Technology Madras, India
Srikkanth Ramachandran
  • Department of Computer Science & Engineering, Indian Institute of Technology Madras, India


We thank Barath Ashok and Suman Sourav for helpful discussions and the anonymous reviewers for their useful feedback.

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John Augustine and Srikkanth Ramachandran. Brief Announcement: Cooperative Guarding in Polygons with Holes. In 1st Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 221, pp. 21:1-21:3, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


We study the Cooperative Guarding problem for polygons with holes in a mobile multi-agents setting. Given a set of agents, initially deployed at a point in a polygon with n vertices and h holes, we require the agents to collaboratively explore and position themselves in such a way that every point in the polygon is visible to at least one agent and that the set of agents are visibly connected. We study the problem under two models of computation, one in which the agents can compute exact distances and angles between two points in its visibility, and one in which agents can only compare distances and angles. In the stronger model, we provide a deterministic O(n) round algorithm to compute such a cooperative guard set while not requiring more than (n + h)/2 agents and O(log n) bits of persistent memory per agent. In the weaker model, we provide an O(n⁴) round algorithm, that does not require more than (n+2h)/2 agents.

Subject Classification

ACM Subject Classification
  • Computing methodologies → Self-organization
  • Mobile Agents
  • Art Gallery Problem
  • Cooperative Guarding


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