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arXiv · 2104.09717

A Recursive Approach to Solving Parity Games in Quasipolynomial Time

Karoliina Lehtinen·Paweł Parys·Sven Schewe·Dominik Wojtczak
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Abstract

Zielonka's classic recursive algorithm for solving parity games is perhaps the simplest among the many existing parity game algorithms. However, its complexity is exponential, while currently the state-of-the-art algorithms have quasipolynomial complexity. Here, we present a modification of Zielonka's classic algorithm that brings its complexity down to $n^{O\left(\log\left(1+\frac{d}{\log n}\right)\right)}$, for parity games of size $n$ with $d$ priorities, in line with previous quasipolynomial-time solutions.

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Karoliina Lehtinen, Paweł Parys, Sven Schewe, Dominik Wojtczak. 2021-04-20. A Recursive Approach to Solving Parity Games in Quasipolynomial Time. https://doi.org/10.46298/lmcs-18(1%3A8)2022

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