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Results tagged with undecidability
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user 153307
Questions about problems which cannot be solved by any Turing machine.
1
vote
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78
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What machines are required to solve the emptiness of regular and context-free langauges?
Consider the language definition:
$L = \{<M>| M$ is a DFA and $M$ accepts some string of the form $ww^{r}$ for some $w\in \Sigma^{*}\}$
The language $L$ is :
A) Regular
B) Context-free but not regular …
- 108
1
vote
Accepted
Is the equivalence problem of a CFG and a FSM decidable?
Yes, your assumption is right regularity of context-free languages is undecidable.
You can look at the problem like this,
If $L(G) = L(A)$ then we can say $L(G) \subseteq L(A)$ and $L(A) \subseteq L(G …
- 108