Overhead-Free Computation, DCFLs, and CFLs

Lane A. Hemaspaandra; Proshanto Mukherji; Till Tantau

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arXiv · cs/0410035

Overhead-Free Computation, DCFLs, and CFLs

Lane A. Hemaspaandra·Proshanto Mukherji·Till Tantau

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Abstract

We study Turing machines that are allowed absolutely no space overhead. The only work space the machines have, beyond the fixed amount of memory implicit in their finite-state control, is that which they can create by cannibalizing the input bits' own space. This model more closely reflects the fixed-sized memory of real computers than does the standard complexity-theoretic model of linear space. Though some context-sensitive languages cannot be accepted by such machines, we show that all context-free languages can be accepted nondeterministically in polynomial time with absolutely no space overhead, and that all deterministic context-free languages can be accepted deterministically in polynomial time with absolutely no space overhead.

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BibTeX RIS

Lane A. Hemaspaandra, Proshanto Mukherji, Till Tantau. 2004-10-15. Overhead-Free Computation, DCFLs, and CFLs. https://arxiv.org/abs/cs/0410035

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