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Results tagged with context-free
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user 64324
Questions about the set of languages (equivalently) described by context-free grammars or accepted by (non-deterministic) pushdown automata.
-2
votes
Is $\{u u^R u : u \in \Sigma^*\}$ context-free?
Based on : Pumping Lemma for Context-Free Languages for reversal language
By @lukas.coenig
{ww$^R$w| w $\in$ {a,b}*} doesn't seem to be a context-free language over $\Sigma$ of length two.
Assumin …
- 62
0
votes
Removing epsilon transition from the grammar. What's the difference between accepting langua...
No difference. You can't re-choose the terminal $A$ after choosing it even once in your example.
- 62