On the Complexity of Free
نویسندگان
چکیده
We locate the complexities of evaluating, of inverting, and of testing membership in the image of, morphisms h : !. By and large, we show these problems complete for classes within NL. Then we develop new properties of nite codes and of nite sets of words, which yield image membership subproblems that are closely tied to the unambiguous space classes found between L and NL.
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