Time and Parallelizability Results for Parity Games with Bounded Treewidth

  title={Time and Parallelizability Results for Parity Games with Bounded Treewidth},
  author={John Fearnley and Sven Schewe},
Parity games are a much researched class of games in NP ∩ CoNP that are not known to be in P. Consequently, researchers have considered specialised algorithms for the case where certain graph parameters are small. In this paper, we show that, if a tree decomposition is provided, then parity games with bounded treewidth can be solved in O(k3k+2 ·n2 ·(d+1)3k) time, where n, k, and d are the size, treewidth, and number of priorities in the parity game. This significantly improves over previously… 

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