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Simple Stochastic Games with Almost-Sure Energy-Parity Objectives are in NP and coNP

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 نشر من قبل Patrick Totzke
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We study stochastic games with energy-parity objectives, which combine quantitative rewards with a qualitative $omega$-regular condition: The maximizer aims to avoid running out of energy while simultaneously satisfying a parity condition. We show that the corresponding almost-sure problem, i.e., checking whether there exists a maximizer strategy that achieves the energy-parity objective with probability $1$ when starting at a given energy level $k$, is decidable and in $NP cap coNP$. The same holds for checking if such a $k$ exists and if a given $k$ is minimal.

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