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As told in this post  we will be having a small discussion tomorrow night – around 8 pm. By tomorrow morning I’ll upload the material and discussions will be based on it. For most part it’ll be on ALU, Pipelining and if time permits Cache and some on Decidability. Any doubts in parsing will also be discussed based on the 3 notes I have made (2 given below under Compiler section and one will be up by tomorrow morning). I’ll mostly take your queries in a Google form which will be made available tomorrow morning. I request you to please go through the below links before asking your queries. Our planned discussion will mostly be restricted to things not covered in the below links. 

Edit: Please add your doubts in Decidability and Parsing (Compilers) here:

I’m also adding all the previous Notes which I have made for GATE CSE here:



Decidability Slides

Last year Discussions: 

Compiler Design:



Mathematical Logic

Previous discussions: 

Graph Theory



Previous discussions: 


Previous Discussions:

CO & Architecture

Previous discussions: 

Operating Systems

Previous discussions:

posted Jan 12 in Study Materials by Veteran (379,263 points)
edited 1 day ago by | 2,220 views


Sir, Is this for specific audience or anybody can join? And how someone will join the discussion?
As told I'll be posting Google form for submitting doubts and anyone can submit. At least tomorrow the actual discussion will be one-way. So, no live participation.

Thanks @Arjun Sir..

Hi Sir,


Thank You for Planning out such discussions from your hectic schedules. As many of us are facing difficulties in answeries questions like as mentioned in the given link.




It will be highly appreciable if you can help us in answering such questions.


And Yes , before tomorrow discussion , i am going to first read from standard books once again and also , will see pages as mentioned by you,


Thanks a lot sir :)


I have added the form to submit your doubts. Today could not complete the compiler notes, so will be doing it one more day.

@Arjun Sir,

any non-trivial property of language is undecidable, 

by non-trivial which is not obvious, 

L(TM) has a string of length 2014 is non-trivial,(sorry but tried how it is non-trivial)

in DBMS 




(I have not posted it in form as it only mentioned to add about parsing and decidability. )

1. DMA 

1. Questions on Burst mode and cycle stealing mode. 

2. What to do if buffer is mentioned and buffer is not mentioned and subsequently the doubt arise about what if buffer size and data to be sent is mentioned.

3. Might be silly but i didn't get it so posting..

Disk access time we use to load into buffer and clock cycle time we used while transfering to main mem. but same doesn't happen in burst mode, there we use disk access time in whole. 

I have gone through whole discussion on GO and Bikram sir beautifully explained it and it gave all the intuition behind DMA but still some of the things are not clear and hence above doubts.

@Arjun Sir, Please add this topic too ( and if possible then above queries too ) as its frequently asked. 


2. TOC ( Reducibility)

Basic things are cleared but still some confusion in how the things actually works. Just flash some light on it  Your intuition will be helpful. 

Sorry, I have to move this till tomorrow. Since most of the queries on Decidability were basic, I will have to start from basic only. @Anirudh Pandey Please add your doubt clearly - I couldnt get what you asked. Also, most of the questions in the blog by @Balaji Jagan are answered in the Rice's theorem page. You can add only the ones you couldnt get.

This week and next week will try to do total 4 discussions. I dont think I'll have time for more, but will ensure that most of you answer 100% from these topics. I know most people skip topics like "Parsing" - but if you see the previous discussions here, those who were discussing these topics are the ones who got into top 100. You must stay ahead of the crowd to become a topper. If you do what everyone does; you will get an average rank and that rank is pretty bad for GATE.  

1. Decidability

2. Pipelining

3. Parsing

4. Cache and Virtual Memory
HI Sir,


Thanks for taking out some time for us. I just wanted to ask the blog which @Balaji Has answered just can you cross check whether they are correct.


Sir,  Except , all parsers and finding whether given parser is LL, LR ,SLR etc... what type of questions are expected ?

Sorry, got some personal issues and just got the slides ready for Decidability. Will be uploading it tomorrow. Thanks to @Sukanya Das and @Subarna Das for helping in the slides. 

Most of the doubts I got are basics - that is why I'm uploading slides. After going through it, if you still have doubts you can ask. 

@HeadShot What type of questions can be asked -- this should be clear from GO book Topics. 


Okay then thats pretty clear.

DMA is much doubful even after whole discussion on GO so it ll be helpful if u flash some light on it as per ur convenience :)

@Arjun sir,Thanks a lot

Sir, please cover polygraph of view serialization.

thanku :) @ sir for these notes really cleared concept of  combinatorics

Thank you sir for your efforts :)

@Arjun sir, where do i find solutions for

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