Re: Is this language context free?



I am sorry. I have no idea why the characters are displayed incorrectly.

The language L = {xyz | x = y^R, z is a string with only c's, and x != z}
Here y^R denotes the string obtained by reversing y.

Thanks,
Dillon


"Chris Smith" <cdsmith@xxxxxxxxx> wrote in message
news:02c579b7$0$2358$c3e8da3@xxxxxxxxxxxxxxxxxxxx
Dillon wrote:
This is a problem I have been working on for a while:

Consider the following language L over the alphabet {a, b, c}. L = {xyz
| x = y^R, z is a string with only c's, and lx|?¨´ lzl }. Here y^R
denotes the string obtained by reversing y.

Is L context free?

You seem to have some corruption in your notation there. What does
"lx|?¨´ lzl" mean? Can you explain it in words?

Without that unknown condition, this language is trivially context-free.

--
Chris Smith


.



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