Phutball Endgames are Hard

Erik D. Demaine; Martin L. Demaine; David Eppstein

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arXiv · cs/0008025

Phutball Endgames are Hard

Erik D. Demaine·Martin L. Demaine·David Eppstein

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Abstract

We show that, in John Conway's board game Phutball (or Philosopher's Football), it is NP-complete to determine whether the current player has a move that immediately wins the game. In contrast, the similar problems of determining whether there is an immediately winning move in checkers, or a move that kings a man, are both solvable in polynomial time.

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Erik D. Demaine, Martin L. Demaine, David Eppstein. 2001-07-27. Phutball Endgames are Hard. https://arxiv.org/abs/cs/0008025

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