{"type":"ScholarlyArticle","title":"Additive AND/OR Graphs","authors":[{"name":"Alberto Martelli","slug":"alberto-martelli","given":"Alberto","family":"Martelli","affiliation":""},{"name":"Ugo Montanari","slug":"ugo-montanari","given":"Ugo","family":"Montanari","affiliation":""}],"abstract":"Additive AND/OR graphs are defined as AND/ /OR graphs without circuits, which can be considered as folded AND/OR trees; i.e. the cost of a common subproblem is added to the cost as many times as the subproblem occurs, but it is computed only once. Additive AND/OR graphs are naturally obtained by reinterpreting the dynamic programming method in the light of the problem-reduction approach. An example of this reduction is given. A top-down and a bottom-up method are proposed for searching additive AND/OR graphs. These methods are, respectively, extensions of the \"arrow\" method proposed by Nilsson for searching AND/OR trees and Dijkstra's algorithm for finding the shortest path. A proof is given that the two methods find an optimal solution whenever a solution exists.","doi":null,"url":"https://ijcai.org/proceedings/1973/1","pdf":"https://ijcai.org/proceedings/1973/0001.pdf","markdown":"https://ijcai.org/proceedings/1973/1.md","bibtex":"https://ijcai.org/proceedings/1973/bibtex/1","volume":{"slug":"1973","title":"Proceedings of the Third International Joint Conference on Artificial Intelligence","short_title":"IJCAI 1973","url":"https://ijcai.org/proceedings/1973/","year":1973,"location":"Stanford, California, USA","dates":"20-23 August 1973","editors":"Nils J. Nilsson","isbn":"","publisher":"International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":"Theory of Heuristic Search","track":"Theory of Heuristic Search","number":1,"pages":{"first":1,"last":10},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}