Lecture 21/65: Equivalence of CFGs and PDAs (part 1)

[@cranberry_sam]

My test is at 4 today, watching these videos help me understand far more than the professor that I pay for. Thank you

[@davidtaylor8144]

Thanks prof i really feel like this just as efficient if not more than sitting in a lecture. I appreciate your dedication to teaching the untaught.

[@JZ_42]

This explains in a much better way than what my textbook does. Thank you so much.

[@The2bdkid]

This is where you would not want the terminals and stack language to share symbols right? Also in a rule with multiple options, like "A -> 0 | 1A" how would you match against that easily?

[@poisonedbanana]

At 5:21, I think "non-terminals" should be replaced with "terminals".

[@sunacha1746]

Thank you so much professor! You are saving my life!

[@doubleyoubee11]

4:46... Left-most derivation. Why does A terminate at epsilon and never terminate at 0? Shouldn't the derived string be 2210epsilon? Or am I missing something because of the ordering? I see: A--> 0A | ε so I would first take A --> 0A which would turn into : [STATE] ε,A-->A [STATE] ε,ε-->0 [STATE] So shouldn't we have 2210 after all that? (and not simply 221?)

[@doubleyoubee11]

I think it just clicked. It is not 2210 because the zero does not matter. The zero does not matter because of the epsilon. Correct, correct?

[@aaronweiss3294]

Those are two rules, and the grammar is non deterministic, you can take whichever you like, every time A comes up. Dr. Porter simply decided not to use the left rule in this particular derivation arbitrarily. 2210 would also be an accepted string.

[@saeshd]

just pick ONE example and finish it for the love of jesus.

[@Kokurorokuko]

what do you mean?

[@saeshd]

this was 8 years ago how dare you do this to me@@Kokurorokuko

[@Kokurorokuko]

​You gotta be ready to defend your words, bro, even 8 years later

[@omargonalfa]

Thank you, great explanation !!

[@TooMuchThought]

So amazingly helpful, thank you so much!!

[@hamedkavousi1706]

Thank you very much sir. It was really insightful and cleared some points to me.

[@richardurena5867]

Thank you for making this video!

[@assermahmoud8571]

thank you it is very good lectures, i want the full course please

[@assermahmoud8571]

i need to know the applications of this field and also i want the recent papers in LL(1)parser if possible, please

[@shaunmike]

rania mahmoud you can find applications of these all over the net

[@silajitsaha3369]

Same as Neso Academy

[@skwisgaarskwigelf331]

I can understand this video. I can't understand shit from Neso Academy.

[@gauravrajghimire6396]

is ur nam really harry porter???? very helpful though thanx