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arXiv · 2404.17530

Lookahead Games and Efficient Determinisation of History-Deterministic B\"uchi Automata

Rohan Acharya·Marcin Jurdziński·Keya Prakash
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Abstract

Our main technical contribution is a polynomial-time determinisation procedure for history-deterministic B\"uchi automata, which settles an open question of Kuperberg and Skrzypczak, 2015. A key conceptual contribution is the lookahead game, which is a variant of Bagnol and Kuperberg's token game, in which Adam is given a fixed lookahead. We prove that the lookahead game is equivalent to the 1-token game. This allows us to show that the 1-token game characterises history-determinism for semantically-deterministic B\"uchi automata, which paves the way to our polynomial-time determinisation procedure.

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Rohan Acharya, Marcin Jurdziński, Keya Prakash. 2024-04-26. Lookahead Games and Efficient Determinisation of History-Deterministic B\"uchi Automata. https://arxiv.org/abs/2404.17530

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