On minimal context-free insertion-deletion systems
نویسنده
چکیده
We investigate the class of context-free insertion-deletion systems. It is known that such systems are universal if the length of the inserted/deleted string is at least three. We show that if this length is bounded to two, then the obtained systems are not universal. We characterise the obtained class and we introduce a new complexity measure for insertion-deletion systems, which permits a better explanation of the obtained results.
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عنوان ژورنال:
- Journal of Automata, Languages and Combinatorics
دوره 12 شماره
صفحات -
تاریخ انتشار 2005