What is a Context-Sensitive Grammar/Language? + Example

Here we define a context-sensitive grammar and language, as well as give an example of a language that is context-sensitive but not context-free: {a^n b^n c^n : n at least 0}. The idea is that a CSG can do exactly what a CFG can do, except that it enforces a "context" in which the rule can be applied.
If you like this content, please consider subscribing to my channel: / @easytheory
▶SEND ME THEORY QUESTIONS◀
[e-mail]
▶ABOUT ME◀
I am a professor of Computer Science, and am passionate about CS theory. I have taught many courses at several different universities, including several sections of undergraduate and graduate theory-level classes.

[@truefaceofevil]

I’ve been attempting to understand CFGs and CSGs a bit better for a while now, and within the first few minutes of your explanation, a lightbulb went on. Thank you!

[@cameronball3998]

This was very helpful! Thank you. My professor and textbook provide almost no examples, so this was very demonstrative.

[@jayk253]

Nice and clear explanation! Thank you a lot

[@powzewu7854]

Thanks for the explanation

[@boriscrisp518]

worlds most complex example expressed verbally for extra difficulty

[@assaydriveby6404]

Awesome video my teacher should really watch this his being fucking up my course

[@con7]

Thank you, better explanation than my prof's by a long shot

[@JohnnyIsTsunami]

Thank you!! This helped a lot with my paper

[@Cowboy8625]

im more confused.

[@اشکانمحمدی-ز1ث]

That's probably because of the algebraic symbols that soon entered the play

[@jwc7285]

explain so well!

[@fatmazahra8191]

thank you for helping
🙏

[@trendystatusforyou]

Great

[@SniperSmiley]

This got me thinking about quaternions i^2 j^2 k^2-> iijjkk-> i(ij)(jk)k->ikik->(ik)^2->(-j)^2->1 so this is context sensitive

[@周品宏-o7w]

(-j)^2 = -1