On the Unmixedness Problems of Colored Pushdown Automata

Recently, we introduced a new automata model, so-called colored finite (CFAs) whose accepting states are multi-colored (i.e., not conventional black-and-white acceptance) in order to classify their input strings into two or more languages, and solved the specific complexity problems concerning color-unmixedness of nondeterministic CFA. That is, UV, UP, UE shown be NLOG-complete, P, NP-complete, respectively. In this paper, apply concept mechanism pushdown show that corresponding versions above-mentioned all undecidable. We also investigate case unambiguous one turns out permanent true (the others remain undecidable).