Leaf languages and string compression
نویسنده
چکیده
Tight connections between leaf languages and strings compressed by straightline programs (SLPs) are established. It is shown that the compressed membership problem for a language L is complete for the leaf language class defined by L via logspace machines. A more difficult variant of the compressed membership problem for L is shown to be complete for the leaf language class defined by L via polynomial time machines. As a corollary, it is shown that there exists a fixed linear visibly pushdown language for which the compressed membership problem is PSPACE-complete. For XML languages, it is shown that the compressed membership problem is coNP-complete. Furthermore it is shown that the embedding problem for SLP-compressed strings is hard for PP (probabilistic polynomial time).
منابع مشابه
Leaf languages and string compression ∗ Markus
Tight connections between leafs languages and strings compressed via straight-line programs (SLPs) are established. It is shown that the compressed membership problem for a language L is complete for the leaf language class defined by L via logspace machines. A more difficult variant of the compressed membership problem for L is shown to be complete for the leaf language class defined by L via ...
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