On the Balancedness of Tree-to-Word Transducers

A language over an alphabet [Formula: see text] of opening ([Formula: text]) and closing brackets, is balanced if it a subset the Dyck text], well-formed all words are prefixes in text]. We show that well-formedness context-free decidable polynomial time, longest common reduced suffix can be computed time. With this at hand we decide for class 2-[Formula: non-linear tree transducers with output whether or not balanced.