id: 06110696 dt: j an: 06110696 au: Dourado, Mitre C.; Penso, Lucia Draque; Rautenbach, Dieter; Szwarcfiter, Jayme L. ti: Reversible iterative graph processes. so: Theor. Comput. Sci. 460, 16-25 (2012). py: 2012 pu: Elsevier Science Publishers, Amsterdam la: EN cc: ut: conquest and expansion games; local majority process; iterative polling process; consensus; dynamic monopoly; reachability problems; finite discrete dynamical systems; local interaction games ci: li: doi:10.1016/j.tcs.2012.05.042 ab: Summary: Given a graph $G$, a function $f:V(G)\to {\Bbb{Z}}$, and an initial 0/1-vertex-labelling $c_{1}:V(G)\to \{0,1\}$, we study an iterative 0/1-vertex-labelling process on $G$ where in each round every vertex $v$ changes its label if and only if at least $f(v)$ neighbours have a different label. For special choices of the values of $f$, such processes model consensus issues and have been studied under names such as local majority processes or iterative polling processes in a large variety of contexts especially in distributed computing. Our contributions concern computational aspects related to the minimum cardinality $r_{f}(G)$ of sets of vertices with initial label 1 such that during the process on G all vertices eventually change their label to 1. Such sets are known as dynamic monopolies or dynamos for short. We establish a hardness result and describe efficient algorithms for restricted instances on paths and cycles. rv: