Distributed Nested Rollout Policy for SameGame

  • Benjamin NegrevergneEmail author
  • Tristan Cazenave
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 818)


Nested Rollout Policy Adaptation (NRPA) is a Monte Carlo search heuristic for puzzles and other optimization problems. It achieves state-of-the-art performance on several games including SameGame. In this paper, we design several parallel and distributed NRPA-based search techniques, and we provide a number of experimental insights about their execution. Finally, we use our best implementation to discover 15 better scores for 20 standard SameGame boards.



Experiments presented in this paper were carried out using the Grid’5000 testbed, supported by a scientific interest group hosted by Inria and including CNRS, RENATER and several universities as well as other organizations (see


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.PSL Université Paris-Dauphine, LAMSADE UMR CNRS 7243Paris Cedex 16France

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