I recently found a question asking whether the language given below is context-free or not:
$L_1 = \{wxyx | w, x, y \in (0 + 1)^+\}$
My intuition is that I can design a non-deterministic push-down automaton for the language. I would appreciate if you could correct me if I am wrong, or brief me on how I could prove that it is indeed context-free.