Lemmings Is PSPACE-Complete
نویسنده
چکیده
Lemmings is a computer puzzle game developed by DMA Design and published by Psygnosis in 1991, in which the player has to guide a tribe of lemming creatures to safety through a hazardous landscape, by assigning them specific skills that modify their behavior in different ways. In this paper we study the optimization problem of saving the highest number of lemmings in a given landscape with a given number of available skills. We prove that, if the number of Builder skills is bounded by a polynomial in the size of the landscape, then the maximization problem belongs to NPO. We also show that, with no such restriction, the game is PSPACE-complete, even if there is only one lemming to save. We thereby settle an open problem posed by Cormode in 2004, and again by
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 586 شماره
صفحات -
تاریخ انتشار 2014