Circuits and Context-Free Languages
نویسندگان
چکیده
Simpler proofs that DAuxPDA-TIME(polynomial) equals LOGDCFL and that SAC 1 equals LOGCFL are given which avoid Sudborough's multi-head au-tomata Sud78]. The rst characterization of LOGDCFL in terms of polynomial proof-tree-size is obtained, using circuits built from the multiplex select gates of FLR96]. The classes L and NC 1 are also characterized by polynomial size such circuits: \self-similar" logarithmic depth captures L, and bounded width captures NC 1 .
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تاریخ انتشار 1999