{"type":"ScholarlyArticle","title":"Algorithms and Complexity Results for Pursuit-Evasion Problems","authors":[{"name":"Richard B. Borie","slug":"richard-b-borie","given":"Richard B.","family":"Borie","affiliation":""},{"name":"Craig A. Tovey","slug":"craig-a-tovey","given":"Craig A.","family":"Tovey","affiliation":""},{"name":"Sven Koenig","slug":"sven-koenig","given":"Sven","family":"Koenig","affiliation":""}],"abstract":"We study pursuit-evasion problems where a number of pursuers have to clear a given graph. We study when polynomial-time algorithms exist to determine how many pursuers are needed to clear a given graph and how a given number of pursuers should move on the graph to clear it with either a minimum sum of their travel distances or minimum task-completion time. We generalize prior work to both unit-width arbitrary-length and unit-length arbitrary-width graphs and derive both algorithms and complexity results for a variety of graph topologies. In this context, we describe a polynomial-time algorithm, called CLEARTHETREE, that is much shorter and algorithmically simpler than the state-of-the-art algorithm for the minimum pursuer problem on trees. Our theoretical research lays a firm theoretical foundation for pursuit evasion on graphs and informs practitioners about which problems are easy and which ones are hard.Richard Borie, Craig Tovey, Sven Koenig","doi":null,"url":"https://ijcai.org/proceedings/2009/21","pdf":"https://ijcai.org/proceedings/2009/0021.pdf","markdown":"https://ijcai.org/proceedings/2009/21.md","bibtex":"https://ijcai.org/proceedings/2009/bibtex/21","volume":{"slug":"2009","title":"Proceedings of the Twenty-First International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2009","url":"https://ijcai.org/proceedings/2009/","year":2009,"location":"Pasadena, California, USA","dates":"","editors":"Hiroaki Kitano","isbn":"","publisher":"International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":null,"track":"","number":21,"pages":{"first":59,"last":65},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}