We show how to calculate the maximum number of edits per character needed to convert any string in one regular language to a string in another language. Our algorithm makes use of a local determinization procedure applicable to a subclass of distance automata. We then show how to calculate the same property when the editing needs to be done in streaming fashion, by a finite state transducer, us...

For each language L ⊆ 2 and non-zero monotonic function t ∶ N → N, we define a language t∗L ⊆ 2 depending only on L and t. We then prove that a language L lies in NL/poly if and only if there exists a polynomially bounded t (as above), such that the projections (t ∗L) ∩ 2 are accepted by nondeterministic finite automata of size polynomial in n. Therefore, proving super-polynomial lower bounds f...