Abstract
In this paper we investigate Szilard languages of IO-grammars. First we show, similar to the proof in Moriya [Information and Control 22 (1973), 139–162], that these languages are context-sensitive. It is known that there are context-free languages L such that no context-free grammar for L has a context-free Szilard language. Since a context-free language L is also an IO-language the question arises if there exists an IO-grammar for L with a context-free Szilard language. To solve this problem we first provide an algorithm which transforms an IO-grammar into a simple normal form. Then it is possible to construct a context-free grammar generating the Szilard language of the normal form IO-grammar. Hence every IO-language has an IO-grammar with a context-free Szilard language.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
