Derivations from a Grammar

TOC: Derivations from a Grammar
This Lecture shows how to derive strings from a given Grammar and how to identify the Languages that can be generated from the given Grammars.
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[@nunemuntalavardhangoud9358]

I think at the end ,the generalized expression should have m>=1 and n>=1

[@arijeetsutradhar5055]

Yahh

[@dontknow4523]

Yeah

[@bvbyballena472]

Yeah

[@harshsonar9346]

yeahh

[@AnxiousDrK]

True

[@psaikiran9831]

Watched these videos and covered syllabus of whole semester in just 3 days. Thanks a lot

[@robertjimenez5608]

i dont really understand the point of that since youre not really going to be able to encode everything properly

[@arpitpathak7917]

i did in 6 hrs
that also today

[@rando9232]

@@arpitpathak7917 I did it in 2 mins. My mother went to make Maggi and I started watching this playlist. I completed it before she was done.

[@oksowhat]

@@robertjimenez5608 point is that this course is useless for 99% of the people, still it is taught for no reason to everyone

[@robertjimenez5608]

@@oksowhat true

[@piratedvirus]

Give this man an Award! Wow 6 months of semester covered in 96 videos...

[@zoxomonocovo]

This was 6 months of semester? This was covered within the first 4 weeks of the semester? Is my degree different?

[@visheshkwatra2279]

@@zoxomonocovo Indian unis man

[@shivanksingh8154]

And I have covered it only 3 days 🤣🤣🤣🤣

[@ayesha5313]

I swear😂

[@chaitanyaphaneendra3111]

get lost

[@jelenavaryukhicheva1197]

Thank you for this channel. You are saving my "Fundamentals of Computer Science" grade and actually give some education on this topic. Unlike my current university. Also m, n >0

[@vscode4232]

Which linearity is this? Ex 1

[@fuzi_blossom]

Sir for the last question for G3 m>=1,n>=1 or m>=0,n>=0?
I suppose it must be 1 as minimum power of ab is 1,1

[@ghyr3740]

sir, you teach us
in a very good manner
this videos are very much helpful for me.
In the lecture m>0 and n>0

[@elyasaf755]

Thank you sir for the videos! they are great!
One mistake though: in example 3, epsilon isn't in the language, therefor m & n can't be equal to 0, it should be m>0 & n > 0.

[@Aimthing]

yaa m and n >= 1 must be

[@programmer6953]

@@Aimthing you are saying yeah and answering completely different answer in here ,commentor says >0 ur saying >=1 which one exactly comments of this videos makes me sick

[@SumanRajak-gb1yh]

@@programmer6953 bro >0 and >=1 is same....🥲

[@kartikamashal6408]

Sir in example 1
Step 2 you substituted the value of "aA"
And again in step 3 but by you didnt substituted in step 4 even its having "aA"

[@dinesh.p8642]

we can take any production rule and use them. But in the end, u need to derive a string by follwoing prodcution rules. Instrutor tookl it coz it is allowed to take. U can try other rules and apply them.

[@pranavnyavanandi9710]

Don't focus too much on that example right now. It is not regular grammar.

[@Debarshi_Choudhury]

m>0 and n>0

[@prateekkaushik5847]

Debarshi Choudhury agreed

[@arijitchatterjee928]

m>=1,n>=1

[@vinjamurisatyakrishna3332]

good observation

[@BetioLopezMenendez4]

You right, it would be m >= 0 and n >= 0 if in the grammar we had A->E and B->E

[@naseer_alam57]

@@arijitchatterjee928 both have same meaning either m>0,n>0 or m>=1,n>=1
Because here m and n both are integers...

[@swathinr4286]

Thank you so much. It's been really helpful for students.

[@Ansari_Zubair]

In example 1 why did not put tha value of aA instead of A in line 3,
Is Answer correct,i think it should be (a**3+n)(b**2+n)..

[@amulyaarun6617]

best learning tutorial channel

[@jr.shivendra4271]

In example-1 the grammer is "regular grammer".. so language generated by it would be regular language.
Here language generated is of type (a^n b^n).which we have already proved irregular by "pumping lemma"....what you say about it ....?????

[@ChristianBurnsShafer]

The techniques used here are not specific to regular grammars.

[@jr.shivendra4271]

Yeah.... Later I realise that..

[@stjgeeks4713]

9:17 I think it would be m>=1 and n>=1

[@peacewalker8030]

Correct me if I am wrong
But in Example - 3
it should be
m >= 1 & n >= 1

[@mahmoodal-bunni9293]

Crystal clear. Well done. Thanks.

[@souvikbanerjee9728]

last problem- m>=1,n>=1

[@kishorkumarkhadka5877]

Could we not generalize L(G3) as {a^+ b^+ } ?
.
a^+ and b^+ meaning the positive closure of a and b respectively .

[@ChristianBurnsShafer]

The generalization you have given is correct.

[@pranavnyavanandi9710]

It's called Kleene Plus operator.

[@paolocatalbas630]

In G1, why did you execute "aA" twice?

[@edutech8909]

Thank you sir! God bless you.

[@raj-nq8ke]

At last >= symbol should be replaced by > as string can't be null by production rule.

[@1839_RAVISHANKARSUMAN]

There's a slight mistake at 9:25 I guess, it should have been { where m>=1 and n>=1 } and not 0

[@joyjitpatra]

In example 1 the result we got is in the form a^nb^n..But we know this language can't be accepted by Finite Automata...I'm confused..Plz explain...

[@jayparekh7598]

Yeah bro you are right.

[@jayparekh7598]

If you got answer then tell me i am also confused.at this.

[@jayparekh7598]

Dude in the G1 it is not the regular grammar because it is not follows rule of neither Left Linear Gramar nor Right Linear Grammar.so generated language can be irregular.i got answer just now😂😂

[@prantobhoumik6586]

no.1 example is not regular...as it gives a->E (efcynol) ,regular language doesnot generate empty symbol for any input. in regular it only gives non terminal or terminal symbol as output belongs to - (V U T) set

[@theindianpaladin]

Thank you. I was struggling with grammar. All doubts cleared

[@fifyfarisha9851]

Thanks for the video sir! I immediately understand your lectures. I have a question. What if it contain S-> SAB | (lamda). What do i do with S?

[@harshitsharma5647]

Thankyou very much Sir for this series 🙂🙂

[@gurpremsingh]

In the first example why did we stop substituting 'aA' for 'aaAb', why perform 'A->∈' after substituting only 2 times?

[@emperorcleon89]

I think you can repeat many times you want as long as the 'aA' exist and you can also end it anytime using 'A->e'. its up to you

[@ashutoshranjan4644]

Is sir correct at the last example?
Value of m and n should be greater than 1 or 0

[@manoramahajare1493]

Nice explanation 😇😇

[@taylorenglish6237]

Thank you so much. You helped this become so clear to me.

[@vishalkumar-ln8kf]

at 9:19 m and n will not be greater and equal to 0 but m and n will be greater than or equal to 1...i.e m>=1 and n>=1

[@PetBuddies]

Yes, you are right, I was going to write in the comment section about this matter, But you already wrote it. this is really important. Can the channel please review and add a comment and pin it to the top, so that in future people may learn the accurate one

[@poojithak3796]

Thank you so much sir .

[@wrestlingkingdom1531]

sir how can we generate production rules if its not given in the question itself can you explain please

[@miracleozioma1476]

Thanks a lot 🙌

[@redrose9089]

I have a doubt in the grammer G1 which u substitute the aA to aaAb for to steps and at the 3rd step why u substitute A->epsilon and why we subsite the A tends to epsilon in the first step of the grammer please explain

[@redrose9089]

And this the in finite grammer or not

[@Doubleagentaron]

is g1 left linear or right linear? 3:00

[@abhishektripathi6560]

right linear

[@adityatyagi898]

At 9:15 there should be n>0, m>0

[@jesselcherian4370]

Sir is there any notes or pdfs of the topics?

[@musicandpoems4620]

Can we keep on substituting aA as aab??????....

[@vedantmondkar9963]

Why aB and Ab can't be genereated at 4:57

[@shaikhmoin849]

Because we got terminal symbols and further expansion is not possible

[@piratesir4450]

For getting the language
We want to stop at some point not go further that's why.

[@merkelwave1654]

thanks again King!

[@ElifArslan-l9g]

thank you

[@mohamadtabbakh9887]

General question: What's the difference between a regular expression and a regular language summary?

[@shravankumarbolisetty3236]

In Ex-3 it should be m>0&n>0.

[@vicodevv]

God bless you!

[@umamanikantaikkurthi]

9:20 i think m>=1 , n>= 1

[@garogarabed6196]

Amazing video man!! Thanks a lot!

[@lovestehloz]

What playlist is this video in?

[@athukutti]

m>0 and n>0 if it >=0 there will be a power like a^0 and Which will be 1 anyway superb class

[@YScript]

Why did he use the same production rule twice? 2:20

[@deanwalker3956]

Thank you.

[@kushwanthkapa2041]

can we write example 3: a+b+ like this

[@anishNath213]

Sir last one L(G3) = { a^m b^n | m>=1 and n>=1 } hoga ???

[@anshgupta8860]

yes

[@samratganguly]

At 2:30 why you didn't further divided aA to aaAb and again you could have divided aA to aaAb and so on...

[@vishalkotwal8552]

bro but it is regular language generated by regular grammer then it should be accepted by finite automata like it is type 3 right and a^nb^n should not be accepted by finite automata

[@rajamurthysraj9636]

Thanks a lot sir......its so helpful to me......

[@suborno9249]

In the scenario when it was aaAbb why havent you used A->€ in there??

[@video5083]

Is , for example string "aAb" a string generated from grammar in example 3, or capital "A" is not allowed to be in final string?

[@ayubi3642]

"A" is a non-terminal symbol which means it cannot be in the final string. Final strings must only have terminal symbols which are "a" and "b" in this case

[@Aditya-kumar-129]

In the last example
A small correction
m>=1, n>=1

[@supersakib62]

CLear CUt EXplanation.. Thanks a lot

[@kevinjeanmichel3824]

what about m+n=2k+1 with k,m,n>=0 ? some idea please

[@DEV-wy8cr]

Sir, I think m>=1 and n>=1
at 9:17

[@siriousllyy]

Thank u sooooo much

[@AhamedKabeer-wn1jb]

THank you Sir..

[@1010ansh]

IN example 2 we can derive 'aab' 'aaabb' and other infinte strings like that if we use A->a or B->b randomly ??

[@ChristianBurnsShafer]

No.

[@siliconmessiah1745]

We can do that in ex 3

[@pragatisahu5047]

Great explanation.

[@aleksjabraka8126]

why did u substitute the 2nd relation twice?

[@JoydeepDasBIT]

Its up to you. We can generate any string using any number of substitutions.

[@Ansari_Zubair]

@@JoydeepDasBIT then why did not do the same at step 4 in example 1

[@gowrigembali6419]

@@Ansari_Zubair that is your wish bro we can complete the step onces also

[@shaikhmoin849]

@@JoydeepDasBIT thanks a lot bro

[@oxysam37]

sir? i think in g3, condition should be m>0,n>0.

[@brilliazz]

Thank you sir

[@m.naveedakram5488]

great work sir

[@denvermaloba71]

Thanks man

[@aditisharma6755]

Sir, in example 3, why m,n=0? a and b to the power will give null and null is not accepted in the language.

[@elsyfernandes9821]

hey.. even i felt the same.. Can you explain me if you have understood ?

[@UtkarshTyagi]

or m>0,n>0

[@liliasade7069]

Sir Please can you help me to find a language generated by this grammars

[@vincenzopalazzo173]

Thanks!

[@gauthamganesh2331]

thank you!

[@ProfessionalTycoons]

can L(G2) be also empty string?

[@josipcuric8767]

No. Non of the productions are of the form X -> ε

[@karmilahanum183]

good explaination!!!!

[@bishalsen1049]

How in L(3) = (a^m ,b^n | m>=0 , n>=0)
I thought it would be L(3)= (a^m, b^n | m>0 , n>0)

[@ChristianBurnsShafer]

Yes, there is an error in the video as many other comments have already made clear.

[@akshintalaakshith4921]

For the last example in the video m>=1 and n>=1

[@sampathkavala6976]

In L(G3),m,n>=1 should be there instead of m,n>=0

[@rishabhsoni40]

sir, in last you said that m,n>=0 how?
they must be >=1

[@genericpurpose7050]

Thanks a lot :)

[@liliasade7069]

Please can anyone help me to find a language generated by this grammars

[@ProfessionalTycoons]

very good video.

[@wissalboulf699]

Thank you so mat
ch

[@yashwanthgowda1517]

I think m and n should be greater than 1 , in the last 9:22

[@gowrivinaykamalakars7818]

In example 3: m>=1 and n>=1

[@shambhurajput2503]

In example 3, you missed lambda for A and B as well.

[@gayatriparikh578]

Sir in question 3 how we get infinite string

[@davidokeke5339]

I think 🤔 it's a recursive process , substituting A-> aA instead of a will continue to give aA until u decide to leave it as a single symbol a

[@csk877]

HOW CAN I GET NOTES

[@mahimarnabhajra376]

Are these examples of regular grammar or just grammar?

[@ChristianBurnsShafer]

These are examples of how to construct a language based on a grammar. The techniques are not limited to regular grammars.

[@yasamindev]

thank you.

[@samarthtandale9121]

So, A Language is - Generated by Grammar, Represented by Regular Expression & Accepted by Automaton. This is what I have got so far ...

[@sadiqsonalkar]

Last sum last step is hard. How come it is equal to 0. It should be greater or equal to 1 . Right??? 🙄🙄

[@mohmmadalishaikh2149]

yes i also have same doubt

[@Vengeance_W]

I think that in the last minute of the video n>0 and m>0 , not equal.

[@khushpreetsingh3797]

Thanku really helpful

[@souravacherjee616]

Is the grammar given in example 2 Right Linear or Left Linear?

[@harshilshah2507]

Left Linear

[@AMANSINGH-mj7lf]

m n should be >=1

[@voice6905]

in example 3 m,n >=1

[@aniketsamudre4895]

m,n should be greater than 0 in example 3

[@supriya3209]

thankyouuuu