I have a question from a test in a Programming Languages class that is confusing me.
Give a context-free grammar to generate the following language
L = { aibjck | 0 <= i <= j <= i + k }
I am completely unfamiliar with this notation. I cant seem to find anything in the book or my notes about it, and I have no idea how to query google for the answer.
If you recognize it, what is it called and what does it mean?
a^i just means a repeated i times. So a^2 = aa, b^10 = bbbbbbbbbb, etc.
Often,
{} means "the set of"| means "such that"I have no idea what a, b, c are. i and j are non-negative numbers, being greater than or equal to zero. Conventionally, those letters are reserved for integers. The fact that
i <= i + k
means that k is also non-negative.
If a, b, and c are reals, then it seems to me that L is just the set of real numbers. However, it seems like a very contrived and elaborate way of specifying it. That would be something like Dr. Evil s plot to kill Austin Powers.
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