Directed Acyclic Graphs (DAGs) in compiler design Explained step by step

In this video, we will discuss about Directed Acyclic Graphs commonly known as DAGs and how to construct directed acyclic graphs (DAGs) in compiler design.
Topics covered in the video-
1) What are Directed Acyclic Graphs?
2) Use of Directed Acyclic Graph for optimizing basic blocks
3) Properties of a Directed Acyclic Graph
4) Applications of a Directed Acyclic Graph
5) Rules for the construction of a Directed Acyclic Graph
6) Problems based on Directed Acyclic Graphs
For details, please watch the video.
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Directed Acyclic Graphs is an important topic for semester examination as well as competitive examinations like GATE, NET etc.
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[@LearnVidFun]

In problem-02, there is no need of writing 'a' two times..That is wrong by mistake! So, please correct it..You may check the correct solution in notes available on the website :)

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KINDLY give direct link of notes also.

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@@NiteshSingh5375 The links for notes are already available in the description of each video :)

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[@dheerajgadwala8874]

at 10:20 in problem 4, why do we need 'd' when we can use 'b'?

[@pavan3046]

Great explanation, thought to just have a glance but the explanation was so good that i forgot about the time and the video was over. Worth watch.

[@nikhil1651998]

From handwriting to the explanation everything is just perfect. Thank you so much for the video. One suggestion though - You can increase your speed & decrease the video time (students prefer less video time lectures)

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THen his video will be less monitized, Basically u can increase the speed... I found many educational channels decrease their video speed for this purpose.

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Seriously very good..... I often like youtube tutorials but you are simply great....

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Thanks a lot dear for your appreciation :) Keep learning :)

[@BiranchiNarayanNayak]

Very well explained in simple and easy way. I am able to understand it very easily being from a non CS branch.

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Thanks a lot buddy for your appreciation..Happy to help you...All the best...Keep learning :)

[@adityapangtey3501]

thank u ,u made it very easy to understand

[@gauravdhasmana166]

Very good and clear explanation sir. I appreciate your teaching.

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Your doing a great job buddy.. quite helpful.. best of luck.. :)

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Awsm explaination.....

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Sir your method are wonderful and best

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Bhai video bahut achi lagi. Thank you.

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You're awesome bro I understood a lot

[@ChandanGupta-oz4ty]

thank you so much your teaching technique is awesome...

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Thanks a lot buddy for your appreciation :) We will keep working hard to make the content available to you people! All the best...Keep learning :)

[@mohitgondaliya8600]

sup...b explaination...thakns dude for save my result..

[@OmitA25]

very nice explanation............

[@varunsaproo4120]

at 27:50, isn't the graph obtained in step 6 cyclic???

[@UkRrh]

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Awesome video yar! Thanks and GOD BLESS YOU

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Thanks a lot buddy for your appreciation and blessings! All the best...Keep learning :)

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bro you deserve more subscriber .nice explanation keep doing.

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Thanks a lot buddy for your love and appreciation :) We will keep working hard to make the content available to you people! All the best...Keep learning :)

[@anuragchowdhury4101]

Very nicely explained.

[@nihalmudhiraj7404]

Thanks, bro Excellent explanation Good examples

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Thanks a lot for liking it...Please share with your friends! All the best.. :)

[@amanchaurasia4645]

Unbelievable sir thanks

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[@sudhamishra9322]

sir ap bhut achha btate h english bi ir hindi bi..verry nice plz upload more vifeos

[@LearnVidFun]

Thanks a lot dear for your appreciation :) Many more videos are coming! They will be uploaded soon! All the best...Keep learning :)

[@vishmayvaidya810]

Great Teaching

[@dalpratapyadav2277]

Nice explanation dude

[@gopeshkhandelwal9823]

can we remove d=b also in problem 4?

[@anjaliverma905]

Really helpful 🤗

[@KajalSingh-fx4jf]

Excellent work ,it seems just awesome 1 day befr exms...thanks alot

[@LearnVidFun]

Happy to help you...All the best! Keep learning :)

[@shruthipatkur3620]

is dag possible to represent in more than one way??

[@anugupta3103]

your handwriting

[@priyuroy1666]

nice explanation........thankyou

[@rajaryan3713]

Sir,your videos are really very helpful.

[@LearnVidFun]

Hey dear...Thanks a lot buddy for your appreciation :) All the best...Keep learning :)

[@manasvinsharma1740]

Best thing is you covered all kinds of question in one video with theory 😃.... But in question 2 there are two duplicate 'a'....

[@farzeb1198]

Love u man!

[@alvinbanerjee8782]

in the second last question. Can we remove d=b and inplace of g=f+d we write g=f+b. In that way we can also remove another statement

[@mohnishpali9339]

nice...i enjoyed the video

[@LearnVidFun]

Thanks...Keep learning :)

[@DigitalInfotainment]

Thanks Brother!! Very well taught..

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Thanks a lot for your appreciation...Keep learning! :)

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1 more thing, your writting is simple but d most attractive i have ever seen

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Thanks buddy for such a nice compliment... :)

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[@LearnVidFun]

Woow...I am glad to hear that! I would love to help you in future as well...Stay tuned! All the best..Keep learning...God bless you :)

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+LearnVidFun thanks again.. n i ll blessed by dt..

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Damn buddy, your handwriting is effing good!

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itna saja saja ke likhenge to 3 ghante ke paper main 10 ghante lag jayege

[@poojapatil1184]

Thankyou for these videos.

[@LearnVidFun]

Keep learning :)

[@trojanhorse8278]

@30:04 we can even reduce one assignment d=b and so the last expression would be g=f+b. Please correct me if I misunderstood.

[@ZUBAIRALI-ex4bu]

is it necessary thats first we create 3 address code then find its DAG or directly we can find DAG????

[@LearnVidFun]

No, it's not necessary for you to first write 3AC when question comes in your exam to draw a DAG for a given expression. You can draw it directly if you can and the question is of less marks....Rest depends on your college faculty...Consult them once! All the best...Keep learning :)

[@dolphinextreme48]

Why do we keep the d=b statement? Is it not redundant? We could replace d with b in the upcoming statements, maybe?

[@afzalali2448]

Awesome bro

[@iamrajagrawal]

Your explanation is too good...Keep it up :)

[@LearnVidFun]

Thanks buddy...Keep learning :)

[@vasubhatt6160]

in problem no. 4 @30:00 why we need d=b?..... because it's redundant, we can use g=f+b in the place of d, then why to keep unnecessary expression d=b? please explain.

[@zeeshanzaheer5109]

luvd it awsome teaching Sir

[@LearnVidFun]

Thanks a lot...Keep learning :)

[@sourabhbanka]

very good video thanks a lot

[@LearnVidFun]

Thanks a lot buddy for your appreciation...Keep learning :)

[@suryapratapsingh7106]

can u plz give an example where we have to use the assignment operator in dag

[@korviyakshith1166]

Tq sir 😍

[@ashu030991]

what a handwriting man ... osumm

[@LearnVidFun]

Thanks a lot buddy.. :)

[@anshulbansal6734]

great and easy explanation...thanks for sharing... but I have a doubt in question no. 3.... after optimising blocks you drew DAG which do not contain line between 'c' and 'f' I didn't get this 2nd DAG

[@LearnVidFun]

I appreciate your learning! Yes, there should should be an edge between 'c' and 'f' for the DAG drawn in problem-4 corresponding to the third statement 'f=a+c' of the optimized code. It has been corrected in the video now! Thanks...All the best..Keep learning! :)

[@prateekghamandi8445]

good explination. please upload more videos of compiler design of topics like sdt

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Thanks for liking the videos....Many more videos are the way...Till then just subscribe yourself and stay tuned! :)

[@shubhamthind8286]

Nice explanation

[@er.gopaljha7758]

nice very helpful.... nd plz upload more compiler construction vedio

[@LearnVidFun]

Thank you so much for liking...Many more videos are on the way...so just subscribe yourself and stay tuned...All the best :)

[@sumitramandal2253]

thank you so much sir

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Happy to help you... Keep learning :)

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u save me :) thankyou so much

[@LearnVidFun]

Happy to help you... Check out the channel for more such videos!! All the best....Keep learning :)

[@vishwanathhosmane3834]

Sir how to draw directed acyclic graph for this expression : -(a+b)*(c+d)+(a+b+c) ?? Plz help.

[@rahulsingh4219]

Awesome explation...😀😁😁

[@LearnVidFun]

Thanks a lot buddy! :)

[@SHIVAMARORABCE]

Good Job the great work.

[@LearnVidFun]

Thank you for your appreciation :)

[@tech_soil3592]

In problem no. 4 , the optimized basic blocks are 1. a=b*c 2. d=b 3. f=a+c 4. g=f+d why don't we eliminate 2 (3 address code) , do we have the need of this code segment .

[@raghunathpalyadaw7187]

Right Sir....

[@rakhisingh516]

Tq so much ....😊

[@LearnVidFun]

Glad to help you dear! All the best...Keep learning :)

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saved my day..

[@LearnVidFun]

All the best...Keep learning! :)

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It's a lovely presentation, brother. It was so informative😍

[@sanjeevkumarsen4838]

nice explanation sir ji

[@aahanaarush181]

its really easy explanation with general terms & also helpful // but one thing i didnt understand it might b my mistake that in QNS 4 you said (b=e //b is assigned to e but i m confused that b assigned to e or E assigned to B ?)

[@LearnVidFun]

Thanks for liking the video! :) Answer to your confusuion: In the statement b=e, '=' is an assignment operator which works from right to left which means that the value of 'e' gets assigned to 'b' and therefore now the value of 'b' becomes equal to 'e'. That is why, at 24:00 in the video, I said "humne b ko e ki value assign kar di hai". I hope now it is absolutely clear to you. Still if you have any doubts, do tell me I'll be happy to help you! All the best...Keep learning :)

[@saurabhrajbhar7337]

there should not be a cycle in DAG but on 11:50 graph contains the cycle why?

[@vivekrai4811]

Thanks

[@mayurtayde3887]

sir s7=s3*s6 already prform ho chuka hai qki yeh operation prfor krnese pailehi dag me aagr observe kreto s3 aur s6 already connect hai * ko phr bhi aapne new node q create kiya direct aapne s1,s4 ke side me s7 q nai likha aap chaho to 1 bar 35.37 pe chk kro.............and correct me if i m wrng

[@tahamaaftab6412]

Thank you so much 😊

[@LearnVidFun]

Happy to help you dear! All the best...Keep learning :)

[@xiaomichina5884]

Very beautiful 😍

[@biswajitsingh8790]

hey bro appreciate ur effort. one request can u please make a video on quadruples,triples and indirect triples?? would be great if u can find some time to make one on this topic!

[@LearnVidFun]

Thanks a lot buddy for your appreciation! I will definitely try to make videos on your given topics too!

[@Nshree282]

i am confused about "dead code" will u plzz explain it with example?

[@LearnVidFun]

Tell me your confusion in detail referring question number and timing in the video! :)

[@atulsharma4848]

Your handwriting is so good

[@LearnVidFun]

Thanks a lot for the appreciation! Glad to help you! All the best...Keep learning :)

[@abhijeetnikam894]

Nice Explaination... :)

[@LearnVidFun]

Thank you :)

[@AmityCSE-]

nicely explained. Thank you

[@LearnVidFun]

Thank you..:)

[@shekhargoud5605]

please send your notes please

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ThankU bhai

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Nice video

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brilliant !!

[@LearnVidFun]

Thanks a lot buddy for the appreciation...!!! All the best...Keep learning :)

[@kashishsingh3211]

thanks

[@rajendrakumardangwal8084]

In problem 2 cant we take 'a' only once for representing 'a + a'.Plsss help.

[@LearnVidFun]

Yes...you are right! In the very starting, we will take only one 'a' to represent 'a+a' because while constructing DAG, a new node will be created only when the node we are about to create does not exists. Please don't be confused. Thank you so much for notifying it! :)

[@udsingh3044]

NICE EXPLANATION

[@LearnVidFun]

Thanks.. :)

[@subrotoroy7646]

how to form a DAG of a negative expression? like in "A=B*-C+B*-C" how will "-C" be represented?

[@LearnVidFun]

Hey dear...Just write a 3 address code for the given expression and then construct the DAG...You will get the solution!! We have already solved such problems...Kindly refer the videos :) All the best...Keep learning :)

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i crave for your Handwriting

[@LearnVidFun]

Thank you so much buddy for your love! And truly speaking, I crave for the lovely comments from all of you :) Stay tuned...!! All the best...Keep learning :)

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Nice sir

[@mahendratamta5615]

Thanks sir..

[@LearnVidFun]

Happy to help you dear :) Stay tuned to watch more videos!! All the best...Keep learning :)

[@satyavineetha7084]

GUD explanation

[@LearnVidFun]

Thank you...Please share with your friends :)

[@rajshrifand3016]

beautiful explained

[@LearnVidFun]

Thanks dear.. :)

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Good explanation thnks

[@LearnVidFun]

Thanks.. :)

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Awesome ...

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Triplings right? :D

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Yashwardhan Pauranik yeah bhai..

[@LearnVidFun]

Thanks buddy.. :)

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best explanation :)

[@LearnVidFun]

Thanks dear! All the best...Keep learning :)

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your everything thing is perfect, from lecture explanation to writing to example. Just one issue is its very very long, you either increase speed or break lectures and examples into two videos. You deserve much more subscriber but i think time is the main issue. I myself hesitating because its 40 min, though seeing in 2x still feels slow.