Most viewed posts in Interview Experience

41

Interview for the post of Scientist/Engineer at ISRO held on 23/02/2018

Reporting time was 8 am. Every interview took approximately 15-20 minutes. After hearing questions from everyone, I felt subjects like Computer Graphics, Software Engineering(specifically testing part), Networks, Information Security, Programming languages were really focused on in the interview. My interview began at around 4.30 pm. There were around 10-15 interviewers.

Q1. Introduce yourself.

Q2. Tell us your favorite subjects (told them DS and algorithms)

Q3. So, are you comfortable with networks? (yes sir)

Q4. Explain the OSI model. What is the function of session layer? What is port forwarding and port mirroring?

Q5. Do you know any protocol which is used at the network layer?(told them Internet Protocol(IP))

Q6. So can you tell us the structure of IPv4?

Q7. So, you told it has TTL. Explain in detail the working of TTL.

Q8. Which programming language do you use? (told them C)

Q9. What do you mean by abstract data type? What is an exception?

Q10. Tell us the difference between Windows based OS vs Linux based OS.

Q11. So, are you comfortable with Information Security ?(Yes Sir)

Q12. Tell us what is phishing? How can you detect/prevent it?

Q13. What do you mean by authentication? Difference between authentication and   authorization. If I am entering a password, what will it be authentication or authorization?

Q14. What is SQL injection attack?

Q15. Explain two factor authentication.

I got Selected.

42

Interview was at ISRO Guest House, Chennai.

Preparation Advice for written test :(most of you already know this) Do not prepare solely for ISRO written test, rather prepare for GATE only. I mean it seriously although it sounds like little arrogant!

Coming to the interview part, We were asked to report at 8:00 AM. There was some document verification which started at around 8:30 or so. After that candidates done with their verification were called for interview parallely.. My turn was second/third..

I entered the Interview room, it was quiet big with around 10 people sitting on 1 side of table with 1 chair in opposite side and a whiteboard at some distance behind the chair. Now, I don't know the name of the Prof/Scientist in the middle, but he was very polite, he greeted me and asked me to sit, then asked to tell a little bit about myself.

 

Following are the questions(not all, but to the best I remember), and the responses I gave there:

Q: What is the project that you have mentioned ?

me: Handwritten Digit Recognition.

Q: How does it work ?

me: told the whole process.

Q: How are the weights of Neural Network adjusted ?

me: told the Gradient descent algorithm. Then they asked Backpropagation algorithm. I told them what I knew but it seemed they wanted to listen something else. They again asked it and I again said the same thing. (Later I came to know that what I was saying was right but I could have been more precise with my terminology).

Tip: Try to be precise with words and terminologies.

Q: Does Gradient Descent always converge ?

me: told them no with the reason.

Q:In what cases it does not converge ?

me: told.

Q: Can you draw sigmoid function on board?

me: Drew. (For those wondering what it is ? It is a useful function in ML especially with Neural Networks)

Tip: Now I don't want you to get that you have to study Machine Learning and do some Machine learning project in order to get through (although It will be good) but the more important thing here is to mention a project which you have seriously studied, because they will dig deep into it. (And according to me, the project part was responsible for my selection! )

The main thing is that with this level of knowledge (which most of you are at) they don't expect you to solve some great real world problem or build a ISRO project , they just expect you to be thorough with your Project (as mentioned above) and with the GATE syllabus (as will be clear below).

The GATE syllabus part.

Q. What are your favourite subjects ?

me: Theory of Computation, Mathematics, Algorithms, Data Structures (I wanted to stop here and not go into system subjects but they kept saying and and...) so I had to say all i.e.,Network, OS, DBMS.

Q: Suppose a user wants to send Application data to another computer. How will the data go?

me: told the process of segmentation, then how the headers are applied etc.

Q:Do you know fields in TCP and IP header ?

me:told

Q:Do you know VPN?

me: I had never studied VPN, but I remembered something from somewhere and answered "It is used to group ports on different switches so that broadcasts can be done to only members of certain group rather than all the hosts on the switch...." I didn't realize that I was telling about VLAN,, so here came the next question :

Q: What is VLAN ? :O

me: Fortunately I remembered by now. I smiled and said that what I just told was VLAN.

Then came some Mathematics questions, but not much.

Q. What is rank of a matrix ?
me: told

Q. What are the applications of rank of a matrix ?

me: told them about its applications in Solving system of equations.

Pretty much that was all.

Final status : Selected!

43

Greetings to all, I am Animesh. I have appeared in GATE 2021 and my gate score was 742 with a rank of 447 General Cat. Here I am posting various questions asked from me in different interviews for MS/M.Tech Research courses.

Note: My interest lies in Machine Learning and AI, that’s why I prepared Linear algebra along with basics of ML for these interviews.

  1. IISC Quantum Technology M.Tech interview questions : https://docs.google.com/document/d/1E9Ta_1zm8nvktaWcKOchMDTh3BWQ-kf2KGilubRlpJc/edit?usp=sharing [This was a new course started by IISC this year(2021), and I had no prior experience in this Quantum Tech field, so I appeared in this interview just for the sake of experience]
  2. IIT Bombay MS TA interview questions : https://docs.google.com/document/d/15A4SsQsc5diSsP6gxR73joAY8yUo6mVGXcYHk6Yy-nQ/edit?usp=sharing
  3. IIT Madras MS interview questions : https://docs.google.com/document/d/1jDsTDYyz7khijZr30PvOmdEup7a5cDy-EW1QYVIYzT4/edit?usp=sharing

I will be adding few other interview experiences(IISC CDS, IIT Bombay MS RAP etc) soon.

44

For 2021 Selection Criteria for IISc CDS: GATE score 70% + 30% written test and interview

Written Test Questions [Total Marks: 40]:    (Time: 1 hour 30 minutes)

There were 5 MCQ Questions, each carrying 5 Marks [5x5=25] from the domain:

  • Linear Algebra (Especially, basic properties of different matrices and eigenvalues)
  • Probability (Classical)
  • Combinatorics
  • Graph Plotting

There were 2 Programming Questions [5+10=15]:

  1. Check if the input array is in strictly non-decreasing order or not. [5 Marks]
  2. The input sample Matrix M is of size n x n. Given, Filter Matrix W is of size m x m. Perform Convolution and find out the output matrix C of size (n-2) x (n-2). [10 Marks]

Interview Experience: https://gateoverflow.in/blog/13537/iisc-bangalore-tech-course-work-interview-experience-2021

 

45

Interview Experience for M.Tech. RA C.S.E. in I.I.T. Hyderabad

My interview was in July 2020. Due to pandemic it was taken online on Microsoft Teams. It was taken by two professors in my panel say P1 and P2.

P1: Hello Shivangi. I am Prof Sathya Peri from CSE Dept. Show your ID Card.

(shown)

P1: Start with your introduction and educational background.

(told)

(As i was working for 1 year now in IT sector so he asked)

P1: Why are you interested in M. Tech. ?

(told)

P1: As we are short in time so we will ask questions now, just explain the concept and don’t write the code for it.

P2: How can we find the middle element in the linked list in O(N) and only one traversal?

As length of the linked list was not given and only one traversal was in condition so he gave me hint to solve with one slow and one fast pointer…solved at last

P1: How can we print values of a BST in decreasing order?

As Inorder traversal of a BST is ascending order so i initially put that in an array and then reversed the array…but later improved the traversal with modification as we can print like Right, Root and Left and this will give descending order.

P1: Have you heard about the famous 2 SUM problem where a sum is given and we have to find pairs in the array which on addition gives that sum?

I knew the O(N) solution of this using hashmap and told him that…he was impressed with that and later he modified the question for BST and for that the similar concept can be used and i was able to solve that also.

Because of time shortage only these questions were being asked.

Result: Selected for Round 2.

Later they gave us a google meet link where they explained about available projects in M.Tech. RA and gave us a google form to fill with our preference by next day before Round 2 interviews.

 

Round 2: On Microsoft Teams

Interview was taken in 2 panels and as per my preference, I had to give interview in both the panels.

Panel 1: All professors with interest in ML and AI field were there.

  1. They asked for the introduction first.
  2. Why M. Tech. after job?
  3. Tell in brief about B. Tech. Project.
  4. What languages you know and how much experience in C/C++ coding?
  5. What is your research interest and then I said machine learning and NLP, so hey asked about any courses that I have done and name of classification algorithms.

Panel 2: All Professors with interest in systems were there.

  1. They asked for the introduction first.
  2. As per my preference in Networking project they asked me basic question from computer network like
    1. What do you remember in CN?… I stated with layers in CN.
    2. Which is your favorite layer?… I said Network layer
    3. He asked me about routing algorithms…Distance vector routing and Link state routing.
    4. Which one is better for large network and why?
    5. What is count to infinity problem?
    6. Experience with programming in college and work… I told about working on JAVA in my job…so he asked which packages do I use in java.

Result: Selected for M2Smart Project

46

2021 GATE Overflow Interview Experience Links.

College Name Interview Experience Blog Link Program Specialization
BARC https://gateoverflow.in/blog/14029/barc-interview-experience-2021 M.Tech. CSE
IISC https://gateoverflow.in/blog/13585/iisc-csa-mtech-reseach-interview-experience-2021 CSA M.Tech. Research CSE
IISC https://gateoverflow.in/blog/13583/iisc-mtech-research-online-written-screening-test-questions CDS M.Tech. Research CSE
IISC https://gateoverflow.in/blog/13558/iisc-research-interview-experience-printing-engineering CDS M.Tech. Research CSE
IISC https://gateoverflow.in/blog/13540/iisc-bangalore-tech-course-work-written-test-questions-2021 CDS M.Tech. Research CSE
IISC https://gateoverflow.in/blog/13537/iisc-bangalore-tech-course-work-interview-experience-2021 CDS M.Tech. Research CSE
IISC https://gateoverflow.in/blog/13453/various-interview-questions-research-programs-iits-iisc-2021 CDS M.Tech. Research CSE
IIT Bombay https://gateoverflow.in/blog/13421/iit-bombay-ms-intelligent-systems-interview-experience MS CSE
IIT Bombay https://gateoverflow.in/blog/13453/various-interview-questions-research-programs-iits-iisc-2021 MS  CSE
IIT Gandhinagar https://gateoverflow.in/blog/13434/iit-gandhinagar-interview-questions-2020 M.Tech. CSE
IIT Gandhinagar https://gateoverflow.in/blog/13356/iit-gandhinagar-mtech-regular-interview-experience-2021 M.Tech. CSE
IIT Indore https://gateoverflow.in/blog/13596/iit-indore-interview MS CSE
IIT Indore https://gateoverflow.in/blog/13476/iit-indore-ms-cse-interview-experience-2021 MS CSE
IIT Indore https://gateoverflow.in/blog/13381/iit-indore-ms-research-cse-interview-2021 MS CSE
IIT Jodhpur https://gateoverflow.in/blog/13532/iit-jodhpur-mtech-cse-interview-experience-self-sponsored M.Tech. CSE
IIT Jodhpur https://gateoverflow.in/blog/13530/jodhpur-self-sponsored-with-fellowship-interview-experience M.Tech. AI
IIT Kharagpur https://gateoverflow.in/blog/13597/iit-kharagpur-ms-interview MS CSE
IIT Madras https://gateoverflow.in/blog/13430/iit-madras-ms-interview-experience MS CSE
IIT Madras https://gateoverflow.in/blog/13423/iit-madras-ms-intelligent-systems-interview-experience MS IS
IIT Madras https://gateoverflow.in/blog/13453/various-interview-questions-research-programs-iits-iisc-2021 M.Tech. CSE
47

I was called in for the interview at 4:21 pm and the interview lasted till 5:22 pm. The interview panel consisted of about 5-6 members. They all sat around a roundtable. For rough work, I was given plain white rough sheets and a pencil.

First of all, they asked me some general questions like when did I arrive in Mumbai, whether I liked the city or not, etc. After that, they told me to write my favorite 5 subjects.

I wrote :

  1. Algorithms and Data Structures
  2. Theory of Computation
  3. Operating Systems
  4. C language
  5. DBMS

 

1. Algorithms

Q1: What all notations are used to find the time complexity of a program?

Q2: Explain all asymptotic notations with their graphs.

Q3: When we write f(n)=Ѳ(n) this means f(n)<= c1*n and f(n)>=c2*n , here is c1==c2?

Q4: Find time complexity :

Void fun1(int n){

int i=1;

int s=i;

while(s<n){

   ++i;

   s=s+i;

   }

  }

  Q5: Consider the C statement int a[], what can be the maximum size of the array?

 

2. Data Structures

Q1: What all data structures can be used to represent graphs? (I told adjacency list and adjacency matrix)

Q2: In which case we prefer adjacency list and in which cases adjacency matrix?

Q3: Draw a graph(any random example), make adjacency list representation of that and also indicate how to represent adjacency list in C language.

 

3. Operating Systems

Q1: An array is a contiguous allocation of memory, but in paging or other memory allocation schemes the array is stored in a discontinuous manner(supposing the size of the array is large).In that case how to retrieve array?

Q2: What is the virtual memory? What are additional things required at the hardware level to implement virtual memory?

Q3: What is re-entrant code?

Q4: Suppose there are two processes and they both have printf() statement. So, the code for the printf() function will be copied in main memory for the execution. This coping of code is done one time or each time the printf() function is being called?

 

4. Theory of Computation

Q1: What are the different types of automata?

Q2: ∑={a,b,c} L=Ending with ab or bc or ca

Identify type of language and draw a FA if possible.

Q3: ∑={0} L=Containing zeros in the multiple of 6

Identify the type of language and draw a FA if possible.

Q4: Write grammar for the unequal number of zeros and ones.

Q5:Is the grammar above, same as the grammar for { 0m1n |m!=n,n>=0,m>=0}.

 

5. C language

Q1: Difference between(in terms of memory allocation) :

 

int a;

                      

struct t{

int a;

};

 

#define a 100

 

Q2: What are macros?

Q3: Write a macro that returns 1 for an even number and 0 for an odd number.

 

6. DBMS

Q1: Draw an ER diagram for the BARC institution where we have two entities Employee and Department where an employee belongs to a single department but a department can have multiple employees. Assume attributes of your own.

Q2: Write an SQL query to retrieve Department name and number of employees in the department.

 

7. Computer Networks

Q1: Explain flow control, congestion control and contention control policies and in which layer of OSI Model they come into the picture.

 

Overall it was a nice experience. The interviewers were very helpful and supporting. Even if you go wrong they give you hints and make you reach the correct answer.

Result selected.

48

 

I'm Abhishek, one of the selected candidates for the BARC OCES/DGFS 2020 Computer Science interview. I was selected through the online written test in which I scored 183.57/300. Total of 87 candidates selected for BARC CS interview. My interview was on 23rd Dec. 2020 at BARC, Mumbai.

Directly, coming to the interview, the panel consists of 6 people and there were 2 different parallel panels that were taking the interview. I entered the cabin and they asked me to sit on the chair.

Then one of the interviewers asked me my name, I answered then he asked: Is this your first time in Bombay, I answered. Then he asked me about my final year B.Tech project, I answered. Then they asked me to tell them some of my favorite subjects. I told Algorithms, Data structures, Operating System, and Compiler Design. One of the interviews asked about my Gate rank and score.

So, these are the other interview questions:

  1. Explain hashing in detail(what is hashing, types of hashing, complete code in C/C++ to insert an element, they asked about time complexity to find an element in open chaining, etc.).
  2. How Binary search works and how it is different from hashing. What is the time complexity of binary search? I told. Why is it logn?
  3. What happens if we divide the array in 3/4th and then use binary search, are comparisons increase, decrease, or remains the same and why?
  4. Given a directed graph, how to detect a cycle in the graph? What is the time complexity of your algorithm by using an adjacency matrix/list?
  5. What is an integer pointer? How it is different from an array of pointers?
  6. Scanning two indices of an array using pointers.
  7. 2-D matrix representation using pointers and accessing elements.
  8. Check whether two strings are the same, less than, or greater than using pointers.
  9. Passing a function name as a parameter to other functions using the concept of pointers.
  10. Explain Wi-Fi architecture, how wi-fi works?
  11. Explain Bluetooth architecture, how it works?
  12. Explain the TCP/IP model, briefly explain any protocol of your choice, how it works?
  13. Explain TCP handshake mechanism(Connection establishment, Data Transfer, Connection Termination phase in detail).
  14. What is Redo/Undo in DBMS?
  15. what is the concept of log files?
  16. What are cursors?
  17. Write an SQL query to find duplicates names from a table given that the Table does not have any primary key.
  18. What is linking and how it is done?
  19. What is the difference between Machine Learning and Deep learning?
  20. What is the difference between regression and Interpolation?

Overall, it was a nice experience and they helped when I got stuck. My interview went for 1 hour and 20 minutes.

That’s it!

Thanks for reading. Hope it helps!

PS: I’m not selected in the final list of candidates. Total of 7 candidates selected for the OCES position. (https://www.barconlineexam.in/engineer/documents/Final-Selection-Engg.pdf)

49
I qualified the written exam of Mtech CS and selected for interview and my interview was scheduled on 15th june 2:30-5:00 pm.
There were 4 professors (as the day was saturday thats why less professor otherwise there can be more on week days) in the class. As I entered in the class they greeted me and offered me to sit, then they asked me about my college and university as they don't know about that, then they asked me about the city also and i told them all these stuffs, then they asked me about my favourite topics in maths and favourite subject , i told them number theory and combinatorics, for cs i said toc, but they said that if they asked from ds and algo will that be a problem for me? Now, as i prepared only for toc but now i can't say also that no don't ask from ds and algo, so i said yes you can ask.
Questions
1) Combinatorics:-As due to rain, the match between the teams in icc world cup got cancelled , So lets the total team be 10, exclude semi finals and finals , consider only league match, tell me the total number of matches that played between the teams such that each team has get exactly one match get cancelled due to rain among them.(I answered this but after hints).
2)34x=43y
Prove that x+y is a composite number.(I solved this but after hints).
3) Graph of cosx vs sinx( I draw the graph and gives correct answer, now they were shocked as i draw within 10 seconds).
4)3cosx vs 4sinx.( After think for 30 seconds, i draw this also and that was also correct).
5)prove that i raise to the power i is a real number( one professor said skip this question.) Still i tried but don't get the answer and skipped that one.
6)Given the array of numbers such that A[i]=i, for all i except when i=t, and A[t]=t+1, Find the t.( I first started writing algo then they asked me to explain my approach first i told that my algo will take O(n), so then they asked can i optimized the algo , then i took some examples and then told them that i will apply binary search which will take O(log n). Then said OK Thank you leave now.

End game:- My rank was 36(general category but seats are 17) in the merit list as i qualified for the interview also, but don't think that only getting name in merit list will give you admission in isi ( as i don't know about this earlier, My only advice to juniors who are giving isi 2020 mtech cs is that just try to score maximum in mma and pcb).
50

My IOCL interview was scheduled on 18th June. I was not so happy with this date as it was a clash with my BARC interview. I decided to leave BARC and completely focus on IOCL. I knew that my technical is already strong so I need not worry about that. The only thing that worried me was GD/GT(one must score at least minimum in this to get selected). From past experiences shared on Quora I came to know that they are focused on current affairs, national schemes and problems. I don’t read news regularly, so all this was a big problem for me. But I still had around 10 days left with me which I thought were sufficient. First I read the list of various schemes introduced by current central govt. After this I read about various major events that took place in the previous few months. I also read about Jammu and Kashmir since I was staying there and they may ask about it. In the end I read about IOCL and a little about oil business.

I reached the interview centre IIPM Gurgaon. In the beginning we were shown presentation about IOCL, package composition etc. After this documents verification was started. This process is very time consuming in IOCL. I have attended interviews at many palces(ONGC,DRDO and ISRO) but nowhere they took as much time as in IOCL. After this I was called for interview.

Interview

I went inside the room and greeted everyone “Good morning”. But it was already past noon. The two mams sitting there started smiling and replied “ Good afternoon beta”. I then realised the blunder that I had made but instead of apologising I just smiled. They asked me to take a seat and then asked the following questions:

  • Tell us about yourself?

An expected one. I answered. Then they asked me about my college and from where I have done my training. My training was in computer networks so the next questions were asked from there

  • What is a hub, switch and Router?

I explained

  • What is OSPF?

I told its full form and its use.

  • Then they ask about its working?

I had forgotten and I mentioned the same.

  • Difference between Machine learning and NLP?

Explained

  • What is MPLS?

I said I don’t know.

  • If you are to choose between programming and networks which one would you choose?

I said programming. I had mentioned my interests as Shell programming, Machine learning.

  • What is Shell programming and what is its use?

Explained with an example. They also asked me to write the code for the example that I gave. I wrote the code on the whiteboard.

  • Will this code run on windows as well?

Explained that it’s meant for only bash shell. By default windows does not have bash shell but there are applications which can make it run.

  • What is natural join

Explained by taking an example

They asked some more questions(2–3) which I don’t remember now. The interview went for around 10 minutes.

Group Discussion

We were given Gender discrimination as the topic to discuss. This topic does not need any preparation. My first point was on Triple Talaq. And then I listened patiently for other people points. I had noted the topic on paper and read the topic again. The topic read Gender discrimination not only female gender discrimination. After this all my points were towards male gender discrimination The others mentioned female gender discrimination. My performance in GD was above my expectations.

Tips for GD:

  • At the minimum try to mention at least 5 points. These points must be at sufficient interval. It should not be like that you say 5 points in the beginning and stay mum for the rest of the process. GD is about active participation
  • Listen to other people views as well
  • If u can start or finish it is definitely a good thing but don’t be to focused on that
  • Don’t repeat other people points. Also don’t just plainly say I agree. Always try to add something.
  • For every topic there are some points which are known to all. Be fast in saying these points

Group Task

Task given: How to boost the tourism industry?

During the GD I neither started the process nor I made the final statement. So I decided to start this time. And along the way I mention some really good points to which everyone agreed. I also said the final solution in this part. GT went even more better than GD.

Result: selected.

Best of luck everyone.

51
  1. Firstly they conduct an Objective type Paper containing about 20  questions (10 GATE Oriented Subjects, 5 from Probability, 5 From Machine Learning and AI).

I attempted 14 out of 20 questions and get shortlisted for further rounds.

       2. There was another written exam ( subjective type) containing 2 Questions of Probability+Algorithm . these 2 questions are too good . if you have the complete knowledge then only you can solve it.  I am able to solve only 1 of them.

 

Based on the Objective paper they shortlist the students for Interview.  

Interview could be in 2 or 3 slots by different panel .

Panel-1 Questions

a>  Your fav. Subjects?

Ans .  Computer Network, Algorithms , Network Security

b> What is DNS?  ANSWERED

c> What is DHCP and how it works?

d>Public and Private key concept?

e> Explain the methodology of RSA?

f> flaws in DHCP?

g> Symmetric and Asymmetric key ?

 

Panel-2 Questions

Not asked about fav. Subjects.

a> meaning of LR(1) and LL(1) Parsers?

b> to find 2nd largest element in unsorted array?

c> output of      unsigned int a= -7;

                         printf(a);

d> will it compile or not   int b=5;

                                       a=(b++ , ++b);

e> Define memory Hierarchy?

f> Registers in Computer System?

 

 

52

About Myself :

BTech in CSE from Ambalika Institute of Management & Technology Lucknow, Uttar Pradesh (2016-2020)

BTech CGPA : 8.03

GATE year: 2020(first attempt)  Score: 539 Marks: 44.6

Before Interview:

I had to submit SOP and I have to mention 3 area of interest with top priority first.

Interview experience

There were atleast 7 professor in the panel and interview went for 30-35 mins.
First Phase:

I : Tell me about yourself, your area of interest

Me: I told about my college and branch my CGPA, area of interests and other things.
 

Second Phase (question related to my area of interest):

First question : Do you know about Bernoulli distribution, tell me it’s mean

second question: Draw cdf for Bernoulli distribution for a probability p=0.6

Third question: Do you know about Binomial distribution, tell me it’s mean and derive it using bernoulli 

Me: I was confused here and he gave me a hint about Linearity of expectation, and then I derived it somehow but I was confused a little bit.

I : He asked one term related to normal distribution and then same term for binomial distribution

Me: I don’t know sir

Other professor asked one question in OS related to virtual memory

I2: Given logical address is 4MB and page table size is 4KB what is PTE size
Me: I was not sure whether this question is correct or not because we need physical address space. While solving question he asked me questions related to what I am doing on paper like what we will get if we divide logical address space by page table size.

(If anyone can help me the above question please comment )

I3: What have you done in Machine Learning, tell me about your experience like what projects you have done
Me: I told them that I have done a ML course by Andrew Ng and I have tried some kaggle competition by learning from various blogs etc.
I also told him that I read a paper by Pro. Kalidas Yatru on Image Processing 
Suddenly, Prof. Yatru appeared on the screen and said me Hi and started asking me that did you work on that paper etc.
I told him that I tried to read that paper and found it very interesting. 

I4: What are random variables( define them) then give me an example
I4: what is sample space and then what is sample space of tossing two coins
I4: okay if I toss a coin infinitely what can you tell me about it’s sample space

Me: Sir it will be countable and then he discussed something related to this

I5:What is centroid and I am given N point how will you find centroid of these points
Me: I gave wrong answer and then he started asking some more confusing question then I said I don’t have any idea

PS – Questions about my final year B.Tech project were also asked.
 

Third Phase (some question from administrative perspective)

I was asked:
what I am doing in the last 3-4 months?

Are you placed?

Did you solved programming questions on websites like hackerrank?

Results:

Only two people have been selected in MS

I was selected for MS Reinforcement learning

I have also given interview for IIT Mandi for MS but result is still pending.

PS : I am not selected in IIT Mandi, but I will share it’s interview experience later.
 

I want to thank you Anuj Sir ( My senior who is currently in MS in IIT Kanpur). He only persuaded me to study GATE and do something better than my peers)

I want say big thanks to Arjun sir and Bikram sir
Your blogs and comments helped me alot and kept my high all the time. I got to know what does it mean to do research. How to study for GATE and how actually solve a questions and why there is no necessity for coachings. I haven’t done any coaching and GateOverflow was enough for the preparation

Thanks for everything sir. 

I read resume of Pragy sir and debasish deka and other professors of IITs  and it truly helped me understand my goals for future
 


 

53

CAUTION:Long post

IIIT Hyderabad Interview Experience and GATE 2018 journey

PART A: GATE 2018 JOURNEY

Hello everyone, I am Hitesh Kaushik. I appeared for GATE 2018 and it was my first attempt. I ended up with a rank of 1824. I hardly managed to complete my syllabus till 15th january 2018. I was strong in theory but didn't got time to practice much questions due to time constraints. These time constraints were enforced because of various factors, lets not discuss those.

I started following Gateoverflow website and FB group seriously from july-aug 2017. I wish I could have done that when i started my preparation in jan 2017.

COACHING

I joined a nearby coaching in the month of jan 2017.When i started my preparation, i had no clue about what strategy to follow and what resources to utilize. It is after I discovered GO, I was on the right track.In my coaching, one of the faculty (lets name him A) was a legend of his subjects.His subjects were Algorithms,TOC,OS,C language,Data Structures,General Aptitude.All logical subjects were beautifully covered by him and I got a strong hold on these subjects.Actually for every concept, he had his own way of explaining it. HE HATED THE WORDS FORMULA, CRAM, etc. More than for myself, I wanted a good rank for him.I will not find such person again in my life.

Now coming to preparation again, the above mentioned subjects were my strong subjects.The weaker ones are COA,CN,Compiler(I didnt studied it at all for GATE),Maths. The subjects in which I was moderately comfortable were Databases,Digital Logic.

After joining GO and getting involved in it, I realised that I could have prepared without coaching.Gateoverflow is enough if someone is confused regarding self study. The reason I am saying GO is enough is because, first of all it is a complete collection of almost all previous year questions and their perfect answers(100% correct).The discussion on each question is what i like the most.Secondly, GO includes the references to all the standard resources for all subjects and topics. 

I still sometimes wonder about the questions on multilevel paging,heirarchical/parallel cache problems and many more.I dont know how I would have learnt these concepts without GO.These are the topics in which most of the students mug up the formulas and end up doing wrong.

I will not cover study references, test series etc. For them you can refer here:https://gateoverflow.in/blog/3813/my-success-story

Remember , consistency is the key. You have to prepare daily.Either make a time table or be disciplined enough.

PART B: IIITH

By this time , I was undergoing 6 months training in the company I got placed in.

After performing miserably in GATE, it was the time for PGEE exam.I didnt prepare anything specially for PGEE after GATE exam, took PGEE with whatever I retained after GATE preparation.

The exam was easy as compared to GATE. The important points in this exam were : no -ve marking, multiple options correct.

After 10 or 15 days, the results were published and I saw my name in the chosen ones.After the results, i had exactly 1 month to prepare for Interview..Due to ongoing job, I was not able to prepare properly for the interview but then I somehow managed to revise 3 subjects: Algorithms, TOC,databases.While discussing with my friends, many of them suggested me not to choose TOC as it is pure theoretical and research based subject and the interviewers may go to any level.But my love for TOC was at some other level.I didn't listened to their advices and went ahead with these choices.

Date: 13th June 2018

Location: IIITH

There were 4 panels(numbered 11,12,13,14) for CSE.Mine was with panel no 13. I saw my name in the list and my turn was 4th. My turn came, I went in.There were 4 panelists.The room was not properly lit.There was a blackboard for solving questions.

Me: A very Good morning to all(with a big fake smile on my face).

Panel: They just nodded.Please have a seat.

Me: Thank you sir

Panel: So whats your name?

Me: Myself Hitesh Kaushik.

Panel: Where are you travelling from?

Me: Sir, I am travelling from Chandigarh.I am excited to be here( again a big fake smile).

Panel: From where did you completed your btech from?

Me: Told college name and place.

Panel: One of them immediately googled the college name to check if it is govt or private.

Panel:Whats your GPA?

Me: 8.28 till 7th sem.

Panel: Why mtech from IIITH? Why not a job?

Me: Gave a properly prepared answer. 

Let me tell you guys, those people were expression-less all the time.I was like "are they numb?"

Panel: what are the subjects you are comfortable in?

Me: (Now i knew how to turn the table) Sir i like theoretical subjects. So i would prefer TOC,algorithms,DBMS.

One from panel : and maths?

Me: Sir i can try maths.

Panel: No just tell your strong ones.

Me:(thinking, isnt that what i told them earlier).Sir TOC,Algorithms,Databases.

Me: SIr you can ask ANYTHING from TOC.

Panel: 2 of them looked at each other.( I started sweating) .

P4 from Panel: Do you know recurrences?

Me: yes sir 

P4: take this chalk and approach the board.Write a recurrence: he dictated T(n)=T(sqrt(n))+1.What will be its answer?

Me: (thinking, are they kidding me?) Wrote O(loglogn).

Panel: How did you arrived at the answer?

Me:(thinking, how the hell can i write a direct answer.I should have solved it step by step) Sir , I will recursively solve this using substitution method and there will be O(loglogn) function calls.

Panel: Do it.

Me: Did it in fraction of seconds.

Panel: They now looked somewhat satisfied for the 1st time.

P2 from panel: can you draw dfa?

Me:(talking to myself in mind, "apna ilaka aa gaya bhidu") yes sir sure.

P2 : draw a dfa for even no.of zeroes with 0,1  as the alphabet.

Me: (now they are seriously making joke of me) drew the transition graph.

P2:OK while nodding in agreement.Draw dfa for even 0 and odd 1.

Me: (By this time I was frustrated by the level of questions) drew it again in moments.

Now P3 interrupts: draw FA for "3rd symbol from right side is 1 on alphabet 0,1".

Me:made NFA for it quickly.

P3: now draw DFA.

Me: I tried with some initial logic.But I knew this question isnt that straight and requires some more thought process.Somehow, made a partially correct DFA(I knew it was 100% wrong).

P3: He looked satisfied bcoz while drawing the dfa, I was moving my hands to show that i am thinking about the transitions and trying to apply some logic.He said it seems correct(I was happy that he didnt noticed that it was not correct).

Meanwhile P4 interrupts: But 101 is getting rejected here.(Now I was caught). I looked at the dfa and said that "yes i think i missed some cases".

P4: ok first draw dfa for "3rd symbol from left is 1".

Me: made it super quickly.

P4: explain its logic.

Me: explained

P4: then why you are facing problem in previous one?

Me: Sir the last 3 places can have 8 possible combinations and because of that the number of states will increase and the logic will change accordingly.I can definitely do it but now I think I am not able to concentrate properly on the board.

Panel: Everyone was nodding in agreement(I felt good).

P1(finally its P1): (he was going through my certificates and marksheets) thank you hitesh, you may leave. He handed my folder and I left.

After coming out, I was not at all happy with the level and number of questions they asked. I thought they will grill me in TOC and Algorithms but nothing like that happened.

I started analyzing my interview. I was sure that as the number of questions were less, hence they are not interested in me.Either they didnt liked my projects(mentioned in resume) or they were not ok with the choice of subjects.

I came home.On 20th june ,results came out. That day I was continously refreshing the portal on my phone.

Suddenly after one refresh, I saw a button named "ACCEPT SEAT".I rubbed my eyes ,again refreshed it, again saw the button.

I WAS SELECTED.

I went to my team director , told him I got selected(I already told him beforehand that if selected, I will leave the company). He said congrats.You can leave the company whenever you want. My bond letter signing was to be done after the completion of my 6 months training which will be completing in july , hence I was free to walk out.

For me , The interview was short and simple.

SPECIAL  THANKS:

  • Arjun suresh sir - for this wonderful platform and amazing answers on GO.You are a role model.
  • Bikram Ballav sir - Sir, we aspirants owe a lot to you.Keep doing this selfless job.
  • Habib mohammed khan - epitome of knowledge, thanks for your perfect answers to toughest questions.
  • Debashish Deka
  • Sachin Mittal
  • Hemant parihar
  • Praveen saini
  • Pooja palod 
  • My friend Ajinkya Jumbad (congrats again man for IITB)
  • and many more

You can always ping me here or on fb. I will be more than happy to help you.

All the best to future GATE and other exam aspirants.

 

 

 

 

 

54

The cutoff for an interview call was 845, for GEN category.

Before the interview, there was a 45 minute test – it had 5 MCQs and two programming questions. The MCQs were:

  1. Identify the graph of sinx*log(|x|)
  2. If we select a number from the first 50 natural numbers, probability that x + 96/x > 50.
  3. 6 distinghuishable balls, 3 boys, make sure each boy has at least one ball. No. of ways?

and two more simple linear algebra questions.

The programming questions were – traverse a matrix in spiral order, traverse a matrix and find out frequency of odd and even elements.

Now, my preferences in the dept were CSL, MARS and DREAM lab, in that order.

My panel had three people – Prof Satish, Prof Yogesh and Prof Lakshmi and the interview began:

Panel: So tell me what do you mean by a sparse matrix?
Me: Told.

Panel: Okay, how will you store a sparse matrix?
Me: [I was pretty blank and discussed for a few minutes before giving up]

Panel: Okay tell me, which is a better way of representing a graph – matrix or list?
Me: It depends on what are the operations that you want to perform on the graph. For something like a BFS, a list is better.

Panel: Explain BFS’s time complexity in both list and graph.
Me: [Done]

Panel: Okay, suppose I am given a set of vertices and I want to check if it forms a path, which would be better?
Me: We could use a BFS to find the path between the vertices.

Panel: No no, we are given the list of vertices, we need to check if it forms a path or not.
Me: A matrix would be better, since we can look up if an edge exists in constant time or not.

Panel: Okay, if I give you p vertices, what would be the time complexity?
Me: We’ll have p queries, each of O(1) time, making it O(p).

Panel: Okay good. How would it work out for a list?
Me: If the lists are sorted, we can find if a neighbour exists or not in logp [I think it was incorrect – binary search cannot be applied on a linked list, but he didn’t seem to mind for some reason], so overall can be done in plogp.

Panel: Okay, if it’s not sorted then?
Me: In the worst case, we might have to traverse till the end of the list.

Panel: If I give you the average degree of a vertex is d, then?
Me: On average, the time complexity would be O(dp)

Panel: Okay, we’ll switch to OS now. What do you know in that?
Me: Virtual memory, synchronisation etc.

Then the ma’am asked very basic questions on virtual memory – what is virtual memory, why do we need it, how does an address translation work, who does it, how are the bits divided, what happens on a context switch, where is the page table base address stored, how does multilevel paging work, what is the advantage of multilevel paging and so on. Overall, quite basic questions.

Next they moved on to synchronisation – the prof asked me to solve readers-writers problem. I was given a Google Doc where I wrote code. The prof then asked a minor variation – suppose we only want to let x amount of readers enter into the CS, how would you do it? This lead to a discussion on counting semaphore, locks, how locks are implemented using TestAndSet, granularity of locks, efficient lock usage and that was it.

In the end, they asked me if I had a MTech offer, to which I said I do, but I am interested in research programmes and it’s only a backup. Then they said why not apply for a PhD and I said I am not sure right now, but would convert from MTech to PhD if I like it. 

That’s all, lasted around 45 minutes on Microsoft Teams.

Verdict: They had received around 2500 applicants, they selected 17 PhD and 7 MTech in the shortlist. Don’t know how many will get converted to final offers. 
 

55

Category: General 
GATE Score: 779
All India Rank: 312

This year the interview process was online due to the COVID-19 outbreak and the cutoff for getting shortlisted for interview was 776 Score (AIR 335) for General category. I interviewed for CC sysadmin RA.

[A day before the interview they asked for our resume and any projects we would like to show to the interview committee]

There were 5-6 interviewers, they first asked about my favourite subject, I said 'Computer Networks'.

Then, they asked basic questions like difference between switch and router, IPv4 and IPv6, frequency band of WiFi, routing algorithms, What is Google OAuth?, etc.

I was able to answer them but 2 to 3 times they had gone too deep like security in IPv4 and IPv6, VLAN, which I wasn't able to answer satisfactorily.

Then, as I had done internship from IIT-B last year, they asked about my work and my experience.

The interviewer laughs and says, “Do you even know how IIT Bombay network works?”
I said, “Yes, I do.” and explained them how the hostels and departments are connected, the campus network forms a private network, and all the packets to the outside (global Internet) are routed through a NAT router. 

The interviewer said, “Yes, good”

Now, comes the interesting part...

[I : Interviewer, M : Me]

I : Which operating system do you use?

M : Sir, I use Ubuntu as a dual boot.

I : Which is the other operating system?

M : Windows 10

I : Which OS did you install first?

M : Windows 10

I : Why?

M : Sir, because I wasn't aware of Linux in my first year

I : What will happen if I install Linux first and then Windows 10?

M : [...after thinking about 5 to 10 seconds...] Sir, I think we have to reconfigure the bootloader

I : Yes, correct

Personally, I think at this point the whole interview turned around in my favour.

Then, they asked whether I know Perl Scripting, Bash scripting, Python scripting, and Web development. I told them I know only the basics of bash scripting and basic python programming and I've done basic web development like HTML and ReactJS.

After this, they asked about my interests, I told blockchain and compilers. They asked if I'm interested in security, I said 'yes'.

Finally, they allowed me to ask any questions from them, I asked "Is there any scope of research in this position?", then they explained for 4-5 minutes that on some security related aspects it is possible, and in other fields it is always possible.

The interview lasted for 25-26 minutes.

Verdict: Selected 😊

I will be joining IIT-B RA as it seems to be the best option for me, feels like a dream come true! 😇

My tips to future aspirants about cracking RA interviews:
Personally, I feel that these interviews DO NOT require any preparation but reading interview experiences and asking the seniors helps a lot to get familiar with the process. They test how much you have played with computers, how much do you know practically. So, my advise to all the engineering students is that please utilize your 4 years, always keep experimenting and be aware of the practical things, that’s the only thing that matters (and yes luck is also a factor, but don’t worry about it as it’s not in your hands).

I would again like to thank @Arjun sir for providing this wonderful platform and for the Facebook group which gave me hope in February that it is still possible to get into your dream college through interviews 😀

56

[ Prior to interview there was coding round containing 5 questions to be solved in 2 hours, I remember 3 of them as given,

1)Finding nth number in a tribonacci series(not given directly that it is tribonacci series but based on initial 7 numbers given, you’ll guess that) and also to take care of overflow for calculating with large values of ‘n’ to score full 100 marks.

2)You’ve a square $n\times n$ chess board, where each entry is either a building or empty, each entry can store 1 unit water when empty. If water is surrounded by buildings from all sides then only it is stored if there is any opening on any side then water will leak and water stored is zero unit, now given such an input square matrix with buildings on it represented by ‘*’, empty entries by ‘.’, calculate the amount of water stored. e.g.,

$\begin{bmatrix} .&*&*&.\\ *&.&.&*\\ *&.&*&.\\ .&*&.&.\\ \end{bmatrix}$would store 3 units of water. $\begin{bmatrix} .&*&*&.\\ *&.&.&*\\ *&.&*&.\\ .&.&*&*\\ \end{bmatrix}$would store 0 units of water.

3)There is an adjacency matrix of a graph, for any vertex, calculate absolute value of difference between in-degree and out-degree, print the larger value and the vertex that possess it. ]

Got the mail for clearing the coding test the same night and the interview was scheduled 2 days after.

I-Interviewer, M-Me

I- You’ve a complete ternary tree, number of leaf nodes are ‘n’, what’s the number of internal nodes?

M- We’ve this relation, $L=I\times(n-1)+1$  ($L$ and $I$ are number of leaf and internal nodes respectively, ‘$n$’ is the ary of the tree)

$n=I\times(3-1)+1$

$I=\frac{n-1}{2}$

The interviewer wasn’t satisfied with me using the direct formula so then I derived the expression and calculated, 

Suppose the height of the tree is h, $L=3^h$

$Total Nodes=L+I=3^0+3^1+3^2+.......+3^h=3^0\times\frac{3^{h+1}-1}{3-1}$

$L+I=\frac{3\times3^{h}-1}{2}=\frac{3\times L-1}{2}$

$2\times (L+I)=3\times L-1$

$I=\frac{L-1}{2}=\frac{n-1}{2}$  (No of leaf nodes are ‘n’)

I- Do you know there are some proof techniques (in algorithms or Computer science, don’t remember exactly which one he said)?

M- No.

I- You’ve two dice, probability that one is even, other is odd?

M- (I asked him if they’re identical, first he said yes then no)

In identical dice, pair (dice1,dice2)$\rightarrow$(a,b) & (b,a) are considered one event while in distinct they’re counted as two events. 

For identical,

favourable cases=$dice1\times dice2=(1,3,5)\times(2,4,6)=3\times3=9$

total cases=$(1)\times(1,2,3,4,5,6)+(2)\times(2,3,4,5,6)+(3)\times(3,4,5,6)+(4)\times(4,5,6)+(5)\times(5,6)+(6)\times(6)$

$=1\times6+1\times5+1\times4+1\times3+1\times2+1\times1=21$

$P=9/21$

For distinct,

favourable cases=$dice1\times dice2=(1,3,5)\times(2,4,6)+(2,4,6)\times(1,3,5)=3\times3+3\times3=18$

total cases=$(1,2,3,4,5,6)\times (1,2,3,4,5,6)=6\times 6=36$

 $P=18/36$

I- Probability that one is even given that one is odd?

M- Let $A$ be the probability than one dice is even and $B$ be the probability that one dice is odd,

$B$ will exclude only three cases (2,2),(4,4) and (6,6) so $P(B)=\frac{33}{36}$ [ B will also exclude (2,4),(2,6),(4,6),(4,2),(6,2),(6,4) cases which I forgot to include that time. ]

$A\cap B$ means one dice is even and one dice is odd which excludes six cases, (1,1),(2,2),(3,3),(4,4),(5,5) and (6,6), so [ will exclude 18 cases in total, (1,3,5)$\times$(2,4,6)+(2,4,6)$\times$(1,3,5)=3$\times$3+3$\times$3=18, I also didn’t take this into account during interview ]

$P(A\cap B)=\frac{30}{36}$

$P(A/B)=\frac{P(A\cap B)}{P(B)}$

            $=30/33$  Ans. 

I- How did you calculate?

M- I gave him the explanation and there were some more discussions and questions into the same and later the professor said that I missed some even even case or something like that, I guess the missed cases that I’ve mentioned before, don’t remember exactly.)

I- You said your research interest as Deep learning right?

M- Yes

I- Draw an AND gate with a single perceptron with activation function as

 $f(x)= +1, x>0$ 

         $ -1, x<0$

M-

 

I- Draw an XOR Gate with single perceptron?

M- (after some calculation and thinking) not possible with single perceptron.

I- Why?

M- Because there are complementary kind of cases like in AND (1,1) producing higher Σwx+b and remaining all cases produce lower but in XOR not like that.

[   the following answer I found on a webpage is quite appropriate- A "single-layer" perceptron can't implement XOR. The reason is because the classes in XOR are not linearly separable. You cannot draw a straight line to separate the points (0,0),(1,1) from the points (0,1),(1,0). ]

(A professor I showed interest in took my interview on phone call after some day of official interview, also he asked me if I can mail my CV)

I- You’re interested in medical applications of AI?

M- Yes.

I- Why you didn’t go for job having a high CGPA?

M- told about something being interested in research and what kind of research I like.

I- Have you done good coding things?

M- Yes.

I- Then, why is your score low in coding test?

M- I told about that there were too many questions with good difficulty level and even solving questions like that on codechef takes quite amount of time for me.

I- So given enough time you would’ve done all?

M- Hopefully more of them.

I- Then he asked me about what was asked in the interview, and since he wasn’t there on the interview panel that day he asked me if he can ask me questions and asked the following.

I- What is the max and min height of a binary tree, I want exact values?

M- (n-1) and $log_2 n$, Skewed tree for max and balanced tree for min.

I- What’ll be the answer if we put the following constraint, at any node, number of nodes in right subtree should be atleast half of the nodes in left subtree?

M- Same answer (n-1) and $log_2 n$, Right skewed tree for max and balanced tree for min still satisfy the given constraint.

I- What about the following constraint, at any node, number of nodes in right subtree should be atleast half of the nodes in left subtree as well as number of nodes in left subtree should be atleast half of the nodes in right subtree?

M- Min height is still same. Max height is $log_{(\frac{3}{2})} n$

[ $R\geq\frac{L}{2}\rightarrow L\leq2R$………….(i)

     $L\geq\frac{R}{2}$…………..(ii)

From (i) and (ii) we get, $\frac{R}{2}\leq L\leq2R$, so L can have min $\frac{R}{2}$ nodes, now choose one node as root out of ‘n’ nodes, let L and R be the number of nodes in left and right subtree

respectively for the root then,L+R=n-1, L=$\frac{R}{2}\rightarrow L=\frac{n-1}{3}, R=\frac{2\times(n-1)}{3}$

For max height again check splitting at the right subtree and so on...which give max height  $log_{(\frac{3}{2})} n$. Although this answer might be wrong and the professor wasn’t enough satisfied it seemed.]

I- What is the proof that your answer is correct, maybe distributing nodes half-half in both left and right tree at some points or as a whole produces max height?

M- Proof I don’t know. but this seems to be correct.

I- In a throw of a dice (a,b), $X$ is a random variable, that takes the larger value, i.e.,

$X=a,a\geq b$

      $=b,a<b$

calculate $P(X=i)$ in terms of ‘i’.

M- $X=1$ only in (1,1), $X=2$ only in (1,2),(2,2),(2,1), $X=3$ only in (1,3),(2,3),(3,3),(3,2),(3,1) and so on…

In general, $X=i$ only in $2\times i-1$ cases.

so $P(X=i)=\frac{2\times i-1}{36}$ (first did silly mistake and told $P(X=i)=\frac{i}{36}$ and then gave the correct answer.)

I- What if you’ve an ‘$n$’ faced dice?

M- Then, $P(X=i)=\frac{2\times i-1}{n^2}$

(P.S.:- Some my answers may not be correct so do check on that. My gate score-744, rank-460, so got shortlisted for coding test then for interview, and finally got the offer.)

 

57
IISc CD-CS written test and interview

 

General info: In IISc M.Tech Research interviews are conducted in a span of 5 days and two sessions every day(morning: 9 am and afternoon: 2 pm). The written test starts at the specified time in the call letter. There are no specific instructions regarding what to do on that day, you need to directly report to the department half an hour before your test time. In each session they first take a written test of about 30 minutes , its result is declared within next half an hour and then they call for an interview based on your preferences.

 

I had CSA interview on the 21st-morning session and CD-CS interview on 22nd May 2018.

 

CSA Written test : 10 Que in 30 minutes.

 

I’d chosen systems so the questions were from the programming, DSA, COA(cache), DBMS, Compiler, OS, probability, and permutation-combination etc. The questions were very basic thus one can easily clear written examination. I also heard that other two streams paper were easy.

 

-> cleared written

 

I was 4th in the queue for the interview.

In the room, there were 8-9 professors, each having their own field of interest.

In starting they read all my details from my application form and then asked questions related to programming [inplace reversal of singly LL] and to program it on the whiteboard. After that they asked some questions related to previous questions.  Then they switched to OS and asked some questions from scheduling and execution of the instruction from basic to advance level . A bit shorter but good experience.

 

----------------------------------------------------

 

CD-CS written test: 22nd May morning session

 

Only one paper for all different labs. They took our lab preference in another form before the test.

 

5 question in 30 minutes

Q1: given partial code for finding node at d distance from the root node and we have to complete the remaining. The question was easy but many of us struggled with the logic to their partial implementation.

Q2:Given two-persons A and B. A work x hours in a day. B starts at 11th day. However, B worked overtime and at the end of 30 days, both A and B get same payment. For this thing to happen what is the max value of X possible.

 

Q3: The question gave outline of the rainbow and of the 7 colors of the rainbow. Then asked that in how many ways we can fill it?

 

Q4: Given a deck of 10 cards numbered 1 to 10. Select 3 cards one by one. Find the probability that selected cards is in increasing order. Eg : {1, 5, 7} or {8, 9, 10} etc

 

Q5: with n vertices and self-loops allowed, how many undirected graphs possible?

 

After some time they declared shortlisted candidates and 7-8 students got selected for systems interview and 15-17 for Data science research from a total of 46 students.

 

->cleared written.

 

I was 3rd in the queue for the interview.

 

In the roundtable, there were three profs. for taking the interview. Like in CSA, first they go through my details from application and option form. Then they began with algorithms. First, they asked about graph coloring problem. Then they asked for diff approaches to the solution and asked me to code it on the whiteboard. They also asked me to explain the code and find it’s time complexity. Then they’d asked about overlapping range problem. So, I gave the algorithm and also implemented the code on board.

Then they switched to OS and asked about scheduling, round robin(what is going on in the background in round robin) and other things related to scheduling and virtual memory. The interview ended here.
58
There were 2 rounds both of which was conducted on Google Meet platform. Initially document verification was done online and then we were alloted to different Panel. There were 3 panels in round 1. The panel which I got consisted of 3 professors. They were Prof. Manish Singh(P1), Prof. Srijith P.K.(P2), and Prof. Maunendra Dasekar(P3).
Round 1 was of 10-15 mins. Only 2 of the 3 professors asked question to me.
P1 - In which dept are u pursuing your B.Tech. Then he asked of I knew the concept of random variables.
Me - Yes Sir
P1 - He shared a google docs link in the chat window and there one question was given. It was:-
X is a random variable which can take values 0,1,2. Given E(X)=1.2. Find the maximum value of E(X^2)
Me - I had to type out the solution and explain each and every line which I have written and how was I approaching the problem. In the end I was able to answer it.
P1:- Are u comfortable with DS and Algorithm.
Me - Yes sir.
P1:- How can we find the kth min from an array of n numbers.
Me - We can sort the array and get the value of kth index.
P1 - Time complexity of the code
Me - O(nlgn)
P1 - any better solution
Me - After thinking for a while i said we can use the concept of partition in quick sort.
P1 - Time complexity
Me - I analysed and got something like O(n^2). (But after the exam I searched and on geeksforgeeks site it was written this approch take O(n) time if implemented.)
P1 - Is there any other way as well which is better.
Me - I could not think of any better way. (There is one more approach using heap which is better).
P3 - Gave a list of numbers in the docs and asked me to find the median of the list of numbers given.
Me - Gave the answer and discussed the two formula for even no. of element case and odd no. of element case in the list.
Round 1 was over and we were said that if selected we would be sent email for 2nd round which would take place around 3pm. I received an email stating I was selected for the round 2 interview.
Round 2 there were 2 panel named panel 4 and panel 5. I was alloted to panel 4 where there were 4 professors namely Prof. Abhinav Kumar(P1), Prof. Vineeth N Balasubramanian(P2), Prof. SaiDhiraj Amuru(P3), and one more professor(P4) whose name I do not remember. Only 2 out of the 4 prof. asked question to me.  Round 2 lasted for 20-25 mins.
P1 - Introduce yourself. And why do u want to pursue M. Tech.
Me - Answered
P1 - Are u comfortable with probability.
Me - Yes Sir.
P1 - Do u know about gaussian random variable.
Me - No sir.
P1 - What random variables do u know.
Me - Binomial, Poisson, Uniform.
P1 - One basic question on conditional probability related to bags and balls without replacement.
Me - Answered that question.
P1 - You said u knew Uniform Random variable. Then given X is a uniform random variable from 0-2 and Y is a uniform Random variable from 1-3. Z ks another random variable which is defined as Z=X+Y. What is the PDF for Z and the graph using which it is represented.
Me - Z will be defined from 0-3 and the graph will be parallel to X axis from 0-3.
P2 - What have u studied in ML like which concept in ML would u be liked u asked about.
Me - Regression.
P2- Do u know Logistic regression.
Me - Not so much clear with the concepts.
P2 - Okay no problem. Do u know linear regression.
Me - Yes sir
P2 - Then tell me which concept we should follow if we want our regression line to be a curve instead to a straight line
Me - Multiple Linear Regression.
P2 - Any other algorithm which u would be liked to ask question about.
Me - Knn classifier
P2 gave me one situation and asked me what should be the value of k bigger, smaller or in between the total range of data.
Answered it.
P2 - Do u know about basis of a vector.
Me - No sir
And the interview was over and then the next day we were sent a list of projects in which we have to fill in our preferences for the project.
For the future aspirants I would recommend everyone to go through probability and linear algebra(especially vectors part) thoroughly and also some basic concept of ML algorithms which u can get by doing some courses online.
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I wrote a blog on quora about my written test and interview experience at IIT Madras. Hope it helps next year aspirants.
https://sktdt.quora.com/IIT-Madras-MS-CSE-Written-test-and-interview

Edit: IIT Delhi M.Tech. in Computer Technology(EET) Interview

https://sktdt.quora.com/IIT-Delhi-M-Tech-in-Computer-Technology-EET-Interview

IISc CSA Intelligent Systems (M.Tech Research) Written Test and Interview

https://sktdt.quora.com/IISc-CSA-Intelligent-Systems-M-Tech-Research-Written-Test-and-Interview

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Primary Interactions:

  • First, they have read out my application, asked about the choices and preference order of departments.
  • Then I was asked about my GPA.
  • Next, they asked me about my future plans and favourite subjects.

Questions:

  1. All the elements of a NxN matrix are 1. Can you guess at least one eigen value, quickly? Give reason in support of your answer.
  2. I is an identity matrix of size NxN. U is a column vector of size Nx1. It is given, $U^TU\neq O$ and $UU^T$ is of size NxN. The following equation holds: $[I - \alpha [UU^T]]U = - U$ where $\alpha$ is a scalar. Find the value of scalar $\alpha$ and also show the derivation.
  3. Write an efficient algorithm to find out the multiplication of a Diagonal Matrix and an Anti-diagonal matrix of size NxN. 
GATE Score (2021): 646   
GPA: 9.53 (Linear Average upto 6th Semester, during the time of interview)
Category: SC
Result: Selected