Solving parity games via priority promotion

  title={Solving parity games via priority promotion},
  author={Massimo Benerecetti and Daniele Dell'Erba and Fabio Mogavero},
  journal={Formal Methods in System Design},
We consider parity games, a special form of two-player infinite-duration games on numerically labeled graphs, whose winning condition requires that the maximal value of a label occurring infinitely often during a play be of some specific parity. The problem of identifying the corresponding winning regions has a rather intriguing status from a complexity theoretic viewpoint, since it belongs to the class $${\textsc {UPTime}} \cap {\textsc {CoUPTime}}$$UPTIME∩COUPTIME, and still open is the… 

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