Pushdown Automaton to Context-Free Grammar Conversion (PDA to CFG)

Here we outline the PDA to CFG conversion, which involves utilizing the "recursive" structure of the PDA we modified in the last video. The variables of the grammar involve going from one state of the PDA to another with the same stack height. Then it is simply modeling what the "base" case is, and how the "inductive" cases will work, all as rules in the CFG.
What is a context-free grammar? It is a set of 4 items: a set of "variables," a set of "terminals," a "start variable," and a set of rules. Each rule must involve a single variable on its "left side", and any combination of variables and terminals on its right side. See • Context-Free Grammars ... for more details.
What is a pushdown automaton? It is a finite state machine, where on each transition, items can be pushed or popped off of a stack it has, which has unlimited height. See • What is a Pushdown Aut... for more details.
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[@qqqqqqqqqqqqqqq67]

PROFESSOR DOES NOT MISS. THANK YOU VERY MUCH !!

[@hostwdamost7804]

This is awesome. Test tomorrow and this explained it so well! Thank you!

[@oblomov4058]

thanks easy theory you helped me a lot to learn

[@berkbuyukdurak7928]

Thank you so much!

[@EasyTheory]

You're very welcome!

[@moeyali123]

Man, this subject is kinda difficult to wrap my head around. Great explanation tho!!

[@RolandChristine-g6z]

Orn Ridge

[@surajjunni1430]

What will be the complexity of this conversion?

[@samjudelson]

Thanks!

[@alecs2056]

I dont find clear what r and s could be in the type 3 rule, i find ok thinking that from q must be an exiting arrow a, \eps -> u and going into q b, u -> \eps but i have to generate a rule for every possible pair r,s or there is another constraint to check?

[@nevilholmes5900]

thanks

[@csstudent6512]

i don't get it :(

[@moeyali123]

🙃

[@moeyali123]

U wanna discuss it? whats ur discord

[@nesrinoobzz906]

​@moeyali123 do u have some examples about this topic ?