The power of randomized logspace with two-way access to the random tape
Posted by Hsien-Chih Chang 張顯之, at cstheory.stackexchange.com,
Let $\mathsf{ZPL}$/$\mathsf{RL}$/$\mathsf{BPL}$ denote the classes of the languages which are accepted (with zero/one-side/two-si…