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Hello Everyone
This post is regarding the admission procedure in IIITD.
So there are two ways to get admission in IIITD(Both exclusive, you cannot through both choices)
1)Gate entry
2)Non Gate entry
 
//if you are a gate entry then u will get stipend else u will not get any stipend(only difference b/w both  the entries)

Gate Entry:-
Screening 1:-
Requirement :- Rank <= 3000 and college percentage>= 75% (As per my knowledge, dont know the exact criteria)
(if you have good rank and low percentage and vice versa, still u can get the call)

Actually they calculate a score in which they take average of the gate score and college percentage of the candidate and if the candidate’s average crosses the cutoff then the candidate is called for further procedure.

formula=(0.5 * gate score + 0.5* college%) 
(last time the cutoff was 71 point something)

Screening 2:-
On 5 may,we were called for interview.Around 350 students were called and there were only 100 seats.

Last time there was no coding round , Only interview was there.

Non Gate Entry:-
Screening 1:-
You need not to get a good rank to get admission through this entry.Only requirement is that u should have a good college percentage.
College percentage must be above 75% (As per my knowledge,last time cut off was 75%).

Screening 2:-
For non gate entry, there were 2 tests on 5 may - first written test and then interview(only those candidates were interviewed who cleared the written test)
Last time around 150-180 students were called,and there were only 35 seats for non gate.

Interview Experience:-
So on 5 may we were called for interview, after spoiling almost every exam I was quite nervous...haha.
There were around 13-14 panels,Each panel had 1 professor and 2 PhD students.
Type of questions varies from panel to panel.Also it depends upon the field of the professor who is taking the interview,(Literally this really matters, I mean if your favourite subjects are same as the professor's field, then you will really  face some good questions, because they will make u stuck at the basic concepts but its not even that hard to crack it).

So my interviewed started from some basic questions like tell me your favourite subjects,to which i replied C,DS,Algo,OS
then the first question was which algorithm would you choose to sort the playing cards and why?
Then they asked about semaphores,mutual exclusion and many more...(ps:- I seriously dont remember any question now)
But i was able to answer all of them correctly.
At the end they asked about my project, but since i was not so confident about my project,So i directly said that i am not too confident in my project as i am in btech 4th year and working on it(Since i wanted to play safe, because i knew  that if they asked about my project ,i will lose the opportunity to get admission)
The professor was okay with it,and he just asked about my project topic only and then i came out of the room.

After  3-4 days, results were announced and i was selected.

About non gate entry exam:-
First u need to solve a written test, difficulty level is moderate, it consists of both aptitude and gate subject questions.
Once u clear it, u have to pass the interview and the interview procedure is same as that of gate entry.
Non gate results were also announced after 3-4 days.

ps:-(i mentioned everything as per my knowledge, dont know the exact criteria)
How i prepared for  interview:-
I just revised my notes thats it.

One simple note:-
I prepared whole heartedly for gate, studied as much as i could, but could not get a good rank in gate.
After that i spoiled other exams too like IIITH and many more.
On the interview day,I was really depressed and nervous and at the time of my interview , i got so nervous that the professor offered me water bottle and said first drink water and then answer...hahahahah.
See, we all work hard , we all want to go to IIT Bombay, but sometimes we do not perform well by any reason but u know what "mehnat kabhi bekar ni jaati", If u could not perform well in one exam, u will perform well in another and if u spoiled that too,then u will perform well in the next one.

1 thing that i will suggest to everyone that "Dont Give Up till the end, keep fighting", sometimes student dont get admission not because they didnt have a good rank but just because they gave up too early and they start thinking of dropping 1 year.
I would suggest dont even think of dropping until all the doors are closed.

I hope this post will help others.
Sorry for all the grammatical mistakes.
this is my first post btw...
and trust me after getting admission in a good college u will realize that "Gate preparation was halwa,khoon to ye log choos rahe h"...hahah (Atleast in IIITD u will definitely realize it).
bcoz IIITD is a world full of Deadlines...hahaha. 

I had applied for both CDS and CSA M. Tech. Research and got called for both. As I could not clear written exams of IITH, IITG, and programming test at IITB, I wasn’t sure about IISc too.

Interviews were conducted over a period of 5 days from 20th May to 24th May. My interview dates were

21st May: CDS (afternoon session)

22nd May: CSA (morning session)

I reached the campus in the morning at 5:30 am. I had to wait up to 1 pm. Till then I roamed the campus 😊

Test started at around 1:30 pm. I shook my head on seeing all the 5 questions. I was able to attempt just 2 with confidence. I had doubts for the 3rd one and other 2 I knew that I did wrong. In all, I totally messed up with the test and as a result, I was shown the exit door. 

Depressed after the CDS test I went to Yeshwantpur to get a room. One of my friends was coming to stay with me. He had his interviews on the next 2 days. Did some rest and then revised my notes to be prepared for the next day. 

CSA had 3 choices of stream – Theory, Systems, and Intelligent Systems. Each stream had some background subjects. I had prepared for Intelligent Systems, which had Linear Algebra and Probability Theory as background subjects. 

The test was scheduled at 9 am. Reached the campus by 7:30 am. Did breakfast at Prakruthi. Entered the exam hall at around 8:20. We had to select a pool before the test. Each pool had particularly designed tests. Test started at 9 am. It contained 10 questions based on probability and linear algebra. All questions were simple. I had doubts about two questions. Results were announced within 20 mins. Two groups of 7 each were selected from 17-18 candidates for intelligent system pool. I was called at 4^th in group one. I don’t know why called in two separate groups.

The interview started at around 10 am. I got called at around 11:30 am. Went inside. Initially nervous a bit. The panel consisted of 3 professors. 

Prof 1: Told me to sit down, while he went to erase the whiteboard.

Me: Thank you sir

Prof 2: Why did you give the highest preference to Astronomy and Astrophysics? It’s really interesting!

(meanwhile, prof 1 joining in the conversation)

Me: (In a complete surprise!) What sir? I didn’t. It must be a mistake.

(Both professors laughed and the atmosphere got lighten.)

Prof 2: Okay, so you did your BTech from Panjab Unversity.

Me: Yes sir.

Prof 2: What’s your cgpa?

Me: 7.13 sir.

Prof 2: You gave Gate 3 times (saying this he read out each of my scores), 432, 473, 692. It’s a quadratic function!

Me: Yes sir (In my mind – nice observation!)

(All this took nearly 4-5 mins)

Prof 2: So Ravi shall we start with Linear Algebra?

Me: Sure sir.

Prof 1: (Signaled me to go to the board) Take a matrix A of size m $\times$ n. What will be the size of $A^{T}$

Me: Told him.

Prof 1: What will be the size of $A^{T}A$?

Me: Told.

Prof 1: Will it be a symmetric matrix?

Me: Yes sir

Prof 1: How? Can you prove it?

Me: (I knew this but at that moment I couldn’t recall) Sorry sir I’m not getting there.

Prof 1: (He sensed the difficulty and asked) What’s the property of a symmetric matrix?

Me: This question was enough to remind me of everything. Did the proof.

Prof 1: If A is a real matrix then eigenvalues of $A^{T}A$ will be real or imaginary?

Me: Real

Prof 1: Take $AA^{T}$ and specify its size.

Me: Wrote on board.

Prof 1: If m > n then will the eigenvalues of $AA^{T}$ be a subset of eigenvalues of $A^{T}A$?

Me: (Didn’t know anything about it, Tried something but couldn’t progress.) Sorry sir, I don’t know this.

Prof 2: What is a random variable?

Me: Explained.

Prof 2: Suppose a coin is tossed. How will you use random variable?

Me: (After thinking for a while) Let X be a random variable that takes value head or tail (wrong)

Prof 2: What type of values a random variable can take?

Me: Numerical. (Oh! then I corrected my previous answer) Let X denote no. of heads i.e. either X = 0 or 1

Prof 2: What distribution does it follow?

Me: Bernoulli distribution

Prof 2: If the probability of Head is ‘p’ then what are the probabilities of X=0 and X=1?

Me: Answered.

Prof 2: Now if the coin is tossed twice then what values can X take?

Me: (Struggled a bit but finally got it) 3 values 0, 1, and 2

Prof 2: Write probabilities for each of the values of the random variable.

Me: Wrote.

Prof 2: What distribution does it follow?

Me: N number of bernoulli trials is binomial distribution. Here N = 2.

Prof 2: Okay, you can go now

Me: Ok sir, thank you!

Total time of the interview was around 15-20 mins. I could not answer one question. I had made my mind that here also I may not get selected. But still, I hoped for positive response.

5^th June was the happiest day of my life – got the offer letter

Rank – 888

Score – 692

Thank you for your patience! I hope it is helpful for future aspirants

So as i begin,

I started my GATE preparation exactly 5 months before the examination, but i was taking coaching from almost 1 year. I never realized the difficulty of this examination until i started studied seriously for the exam. i was able to complete 60-70% of my syllabus (except subjects like discrete maths – which still haunts me) and my test series accuracy was 70-75%. On the exam day, i was very nervous and the exam temperament hit me so hard that i did very silly mistakes which obviously cost me too much.

I was very depressed for a month but later thought of giving a try at the other examinations and started preparing for it. And then MY HARD-WORK PAID OFF

I got selected for interview for IIIT-H ..I rubbed my eyes almost 5 times to check if it was true or was i dreaming. Yes it’s true and then i decided not to lose this opportunity.

On the interview day, while people around me very nervous, i was confident and happy that i made it till the interview round (the only thought i had in my mind is to make my thoughts speak loud and try to answer questions as much as possible)

SO the interview began:

(i will list the questions asked)

1. Where are you from?
2. Whats your CGPA?
3. What are your favourite subjects (ans: DS, Algorithms, OS)
4. Go to the whiteboard and sort an array using stack ..Done
5. Given an array of elements how will you find the duplicates .. Answered 2 approaches
6. One of the answer was hashing, what if the elements size is huge? ...Answered 
7. Then asked about my mini-project and gave a question based on it
8. Given a classroom and start and finish time array, max the no of slots that can be used ( tried answering but got stuck in between..they helped me ) (btw it can be done using a greedy approach)
9. Questions about OS:
   1. what is virtualization ….answered
   2. is virtual memory s/w or h/w implemented …...answered
   3. difference between cache and virtual memory ..answered  (and 3 more questions that i don’t remember)

      10. What is a rank of the matrix

       11. Where it can be used

       12. Why M.tech and why not MS

So this is how the interview ended. I had a great time in the interview room

Verdict : Got selected for M.Tech CSE

Conclusion  : the reason for writing this blog is just to tell people that your hard-work never goes waste. Keep trying, you will definitely get what you want. Please don’t give up if you fail, just remember you can come up strong every time you fall.

All the best to everyone who is reading this!!

My background: BE in E&TC with 2 years of experience with Tata Elxsi where I worked on computer vision algorithms for ADAS domain. Left the job three months before GATE-19.

PGEE entrance :

The registration for the exam begins usually in 1st week of March. The exam for the year 2019 was held on 29th of April. The syllabus for the exam is mentioned on IIIT-H’s website and is updated every year. Though they do not give comprehensive syllabus, we are expected to cover the topics based on GATE syllabus.

Exam pattern : The pattern seems to vary, but not every year. This years' pattern was different than the last year in the sense that there were no multiple-answer questions this year.

Aptitude section: 90 min, 45 questions (2 marks each)

Technical section: 90 min, 30(2 marks each) + 30(1 mark each)

My preparation for PGEE :

For covering technical section I went back to my notes for revision that I had prepared during my Gate preparation. For practice, I didn’t have any test series' active account as they are revoked after the Gate exam. So I took to solving previous Gate questions and some free available sample questions. For this I referred GO book and geeksforgeeks as they have topic-wise previous year questions as well as some practice questions according to Gate syllabus. Covering previous year Gate questions is a must as some of them are asked as it is in the exam which will not only save your time in exam but also help you in scoring well.

Aptitude section : This section is of 90 minutes. Hence fair bit of emphasis is put on aptitude. Also, the technical section is evaluated only if one clears aptitude section. I referred indiabix.com for covering aptitude topics as I only wanted to brush-up and get some practice. If somebody wants to study(meaning how you approach a certain type of problem) for aptitude, this might not be the right website as they do not provide the 'theory' behind topics and the formulae given are anyway of no use as you need not remember them. Hence refer this site only if you want to get some practice for aptitude, otherwise go with some standard book which covers 'theory’ (meaning how you approach a certain type of problem) and for practice. 

Note: Along with accuracy, speed is very important in the aptitude section.

The result of PGEE was declared within two weeks of the exam.

Interview :

Preparation : To start with, I referred previous year interview experiences available on PGEE Facebook group. This helped me to understand the pattern of interview and the abilities/topics they put emphasis on. 

I did my preparation with three broad areas in my mind : 

General questions : This included questions related to my profile. For ex. Why did I leave my job, why am I turning to CSE after doing BE in E&TC, why did I only opt for M.Tech and not MS. (and vice-versa, accordingly). The questions to prepare for, would be entirely based on individuals' profile.

CS subjects : It is advised to prepare at-least three subjects thoroughly. In the interview, you will be usually asked about the topic which you are comfortable with. I prepared for DS-Algorithm, OS and COA. It is advised to have Data structure-Algorithm as one of the three topics as they are anyway asked about.

Project work: This included preparing the projects I did while working with Elxsi and during my bachelors degree. I prepared for this based on organization of my resume. Since we are asked to submit resume during the registration itself, there is possibility that you might want to make some changes to your resume from the one available with them. Hence take copies of updated resume with you and if required ask them to consider this latest resume. I had to make some changes in mine, though they were not major so did not ask them outright to consider the one I was carrying. And anyway it did not affect the type of questions I was asked.

Doubts, for candidates appearing for interview :

I was called for interview on 13th  June, which was 4th  and final day of the interview process. All the candidates were distributed among 4 interview panels, with each panel interviewing 28-29 candidates. This was the case on all 4 days. 

We were to report at 8 am to Himalaya Building and were asked to sit in bodh-105 where the interview process was explained to us. The professor briefing us about the process cleared many doubts which I would like to mention here as they occur to almost all the candidates going for the interview.

• The interview dates are not given based on merit but are randomly assigned. So the one's called on later dates need not think that they are down in merit list or the one's called earlier are higher in the list.

• During interview, the panel do not refer to your Gate score as parameter for selection though they might inquire about it (you have option to mention it in the application form during registration).

• There will be no waiting-list at-least for the 2019-20 batch. The number of candidates to be selected are not fixed though they do have an upper cap on it.

• If you did not mention MS as an option in your application form but would like to be considered for it, you can tell this to the panel during the interview.

• The duration of interview has no resemblance to selection or rejection of a candidate.

• If you have time constraint on your return journey on the interview day and are allotted a slot later in the day, you can ask them to be interviewed before others. Though the reason must be genuine.

Finally, the interview :

I was in the list of panel-3 who were conducting interviews in Kohli Auditorium. There were three professors in the panel(supposed to be four, but one of them left while I was waiting outside for my turn). Hereon I will refer to the professors as P1, P2, P3. 

I entered the room and wished them for the morning.

P1 (asked for the folder of docs that I was carrying) : (Surprised), So you were working in Elxsi. Why did you leave such a job?

(This was more of an exclamation than a question).

Me- Gave my reasons.

Still he persisted with the question and asked me to explain the job profile (based on the experience letter attached in my folder) which turned out to be a sinner as the next thing he said was "You left a kind of job profile on which we do our research here. You were working in one of the emerging fields." And I must say, this was in no way a compliment but an utter exclamation. He was, in a way, displeased with my decision of leaving such a job. P1 asked me my Gate rank and said "you could have got this rank even while working" which did not help my confidence. After some more discussion they decided to move on.

P2 asked me related to my project mentioned in the resume. Again it turned into a discussion. They did not ask me questions based on implementation ( and I had emphasized a lot more on revising the implementation during my preparation) but on general scope of the application and improvisations that could be done. P2 explicitly mentioned "to think w.r.t research". I put some good points and some very silly one's which made them laugh as well. After another 'discussion' between us, they seemed satisfied and decided to move to some CS.

P1 asked me which topic I would like to be questioned on. ( I can't remember the exact word he used, but it was something which confused me whether he meant a broader topic which I worked on during my job or CS topics, as I was still in my "job" zone, contemplating the previous questions).

With confused face, I replied him with "Data structures and algorithms?" I realized its important to stay simple and calm when asked for choices.

P1 : How will you find if two strings are anagram?

Me : Gave a solution which he was convinced with.

P1 : Given two strings, find if one is rotated version of other and if yes, then by how many places?

I gave an algorithm flow, for which he took time to find a counter example on which it won't work. Meanwhile, he asked P3 to ask me few questions.

P3 asked me to draw graph of y = 1/x and then y = 1/|x|. I drew them.

By this time, P1 gave me a string on which the the algorithm won't work. I had not taken care for repeated characters and I adjusted the algorithm accordingly. Probably, wasn't the cleanest solution, as he seemed to be expecting some more improvisation in it. (Later I checked that though the algorithm started correctly, there are faster ways to find the solution if we start comparing the characters from both the ends of strings. For str2, by 'ends'  means taking 1st char from str1 and finding its 1st occurrence in str2 and then continuing with comparison from both the ends).

Anyways, there are other ways to solve this and am not sure if they were expecting other solutions or the same with some improvements.

Then they said that they were done with their questions and that I can leave. They offered me chocolate which were kept on the table in a tray. I wished good day to them and left.

It lasted for around 18-20 minutes (I checked the time before going in and after coming out 😛 , though the duration of interview has no relation to selection or rejection).

There were positives as well as negatives in my interview. I gave myself 60-70% chance probably because of the way the interview started and few laughs they had, and based on the solution to last question.

After my performance in Gate-19, this was the last chance I had, to get into one of the institutes of my choice. The result was declared on 18th, the 5th day after the interview. I logged in to the portal and saw a “Yes” in the “Interview selection” tab. Elation!!!

I would just say to "fight till the end". Even though I had messed up my Gate, I knew I was better. But that's another struggle. I would limit this post to PGEE and IIIT-H.

Thank you.

After 6 months of preparation of gate along with my software development job . I was screwed in my gate exam( venn diagram question of 2 marks, of which I found out correct answer but I don't know how other option got ticked which I came to know after seeing response sheet and also I missed the question to find out 2s compliment as when I reached that it was just 20 secs remaining) the paper was very easy hence I slipped my rank and landed on 1454 rank and I know iit was only a dream now. That 3 4 marks silly mistakes costed me my iit dream.

Then there was iiith pgee exam a month later. seriously , i didn't prepared for it(because workload was too high as I took 1 month leave already for gate). Still I was able to clear the written and reason I think was the aptitude section. I had prepared for cat in my bachelor's so the quant and english was a cakewalk for me and technical section was also too easy as compared to gate.The thing here is you have to clear both sections aptitude and technical to be called for interview.Hence prepare for aptitude and english too if you are not strong in that.

Now as I know the date of interview was 13 June I resigned my job and got free till end of may and had around 10-11 days for interview preparation.

First I started reading previous year interview experinces from pgee fb group and response sheets of previous year and made a list of topics subject wise from which questions were asked and then allocated a day for each subject.Following is the list

1)C and DS - array heap tree fib heap,c struct pointers , Avl Red black tree,print all elem in Bt with no siblings  -monday

2)Algorithm-algo bfs dfs, sorting ,dynamic prog / divide n conquer,branch and bound knapsack, tree forest,prim krushkal ,dag dijkstra - Tuesday

3)OS- os process execution link load first fit best fit semaphonre -  Wednesday

4)DBMS-dbms lock  primary foreign keys fd,normalization - Thursday

5)Discrete -maths divide rules,  sets relation fnction, vectors,matrix, rank inverse ,determ, 0 eigen values,mead median mode- Friday

6)network &Probab -probab coins and names question and dictionary, bayes theorem mutually exclusive events- Saturday

7)Graph Theory- graph for functions ,paths sets , independent set, edge cover, vertex cover- Sunday

8)Miscellaneous-mails from and without browser,network,tcp ip, functioning when we search google.com ,network 127.0.0.1

lines ,circle, eqation graphs of functions , toghest code written, last sem subjects . Monday

I first revised the subject in whole day and then the topics which are asked again in night. Now in this way I covered almost all topics till 10 .on 11th I read miscellaneous things and had reservation from pune to Hyderabad(which was rac so I was hell lot tired as I was not able to sleep in whole night journey).

I already had friends in Hyderabad but the thing I did was booked a hotel for 12th to 13 as I already stayed with my friend during interview of iitb and iisc and we just talked till 2 in night as we met after a long long time, so I decided to book a hotel for a day before interview(got an ac room in 260 rs courtesy Oyo ) and then stayed with my friends after interview for 3 4 days and visited Hyderabad too.

The Day before Interview- I reached my hotel my sharing an auto from railway station to iiith . Then I checked in and had lunch and slept 3 4 hours in afternoon .Then i studied in hotel room , revised short notes till 1 and went to sleep . 

The D Day- I woke up at 7 , took bath and went for interview There I had breakfast in college itself. There first verification was done and then called according to some sequence in 4 panels . I was 7th in 3rd panel and there were around 30 candidates in each panel.

I was calm and confident. I went in room there were 5 interviewers. They took my resume and asked about my work experience. I had 1.2 yrs of front end development in amdocs . Then they asked what you did from July2017 to march 2018 . I said our joinings were late so we just enjoyed. They asked how I was placed. I said campus placement.

Now came the turning point . The third interviewer asked me about difference of JavaScript and java . I didn't came with a strong answer. Then they asked me about why js is used in Front end. I said it is evolving and new Frameworks are continuously coming but seems he was not satisfied with my answer(I later searched and found out that js is not compiled. It is executed directly and a script)

Now the 2nd interviewer asked me my favorite subjects . I said algo data structures. He asked how many data structures I know . I said tree graph , trie, array , stack queue etc. He asked whether you know about hashing. I said I don't know much in dept about hashing but you can ask me about linked list and algorithms.

Till this time I thought I had screwed a lot but still I carried out. He asked me to find the nth element from end of single link list .I already knew it and told. Then if link list is doubly , no of steps taken to find kth step from end(n-k +2k). Now he asked how can we find a pair of number that sum to a specific value in array. I said one is brute force other is by sorting. He then gave me chalk and told to write full code line by line of brute force which I did. There were some silly mistakes like i=0 to i=n which they all laughed. He asked me another approach , i told we can sort array and start with checking sum if extremes to the given value. then he interrupted as he thought I knew which I did.

Now again 2nd interviewer gave me pen and paper and asked me to draw graph of logx and x =y. I drawed it incorrectly so he told me to check if it's correct. I had made log 0 =0 . But then I corrected and told that i was a little nervous. He told me to chill and again asked to draw the graph of log x to the base 2 log x to the base 3 and difference between them .

Then they told me I can leave and take choclate. I asked it was done and they said yes. I told it was great meeting and talking with you and they said same.

Later I went charminar enjoyed biryani and stayed 3 4 days with my friends in Hyderabad and came home.

Seriously I had not much hope as other people might have given their best and I was not able to differentiate between java and JavaScript. I was just ready to go to nitk for admission on 20 and on 18 result came and I was selected for mtech cse in iiith. It was really a dream come true . I cannot just control my happiness and emotions. I told my parents and friend and went to temple to pray and offer prashad .

For pgee you should prepare aptitude english and maths as it is compulsory to clear it's cutoff rest you will clear if you studied properly for gate . Now coming to interview just go through previous interview experinces . Revise all major subjects and then the topics which have been asked previously.

My advice to aspirants of gate and pgee is sometimes things go wrong but keep trying. Hard work always pays off.

After Gate not going as per my expectations I had my only hopes left for IIITH.. 

28th April 2019

The day for the written test.. The aptitude part was easy and I think practicing questions from india Bix is sufficient for it.. For the 2^nd paper the previous year questions are sufficient and I guess 90% paper was from that only. After the paper I was pretty sure that I will be called for the interview as I had answered all the questions (margin of careless mistakes may be 2 or 3).. So when the result came I was really happy!1

13^th June 2019

The day of the interview.. We were sitting there from 8:00 am .. We had our orientation followed by the biometric verification… Then we were sent back to the hall to wait for our turn .. My serial number was 18 and panel number was 2.. My chance for the interview came at 3:15 pm..

The panel consisted of three professors .. Let us say P1,P2 and P3.

P1: What is your name?

Me: Anjali Bhatnagar

P2: Why Mtech and why not job?

Me: Sir because I have theoretical knowledge and not much practical knowledge so I want to work more on that and then job.. I want to explore various areas and then choose the best opyion for me.

P2: What is your gate rank and gpa?

Me: My gate rank is 498 and gpa is 8.17.

P2: So what are your favourite subjects?

Me: Algorithms,Data Structure , TOC,DBMS and OS.

P2: quite a long list..

P1: Okay go to the board and draw an antisymmetric matrix..

Me: I drew it and told that for it Aij=-Aji..

P1:Why are the diagonal elements zero?

Me : because for diagonal elements i=j so only possibilty for the condition to be true is that the diagonal elements are zero.

P1: So how will u store it ?

Me: we will require n( n-1)/2 sized array to store the elements .. they asked the logic behind it and I explained it to them..

P2: Okay erase the board.So we have 2 computers and 1 router we are sending the packet from c1 to c2 through the router.. Probability that the packet is transmitted is 0.7.. If we transfer one packet then what is the probablility it will reach.. then for 2 packets that atleast one will reach, that not even one will reach.. 

There was a lot of cross questioning but at the end they were satisfied by the method and the ans!

P3: So u r good at programming(In my resume I had mentioned that I am good at programming).. Go to the board and write your complete name .. Write a program in any programming lang in which you r comfortable to tell the index of the character which occurs first for more than 2 times.

Me: I wrote the code and they were satisfied with it..

P1:U r good for MS.. Why didnt u opt for MS?

Me: Sir because I dont have much knowledge about the research area which I should opt for ..

P2: But you have to choose your research area after 6 months.. 

Me: Yes Sir.. I didnt know about this earlier..

P3: So if  you are offered MS will u take it..

Me: Yes Sir..(I was a bit reluctant to answer yes)

P3: Do u have any other admission offers?

Me:Yes Sir from IIITB

P3: Ok good.. Take a toffee and you may leave 

Me: Thank you Sir..

When I came out it was around 3:45pm.. I was very tensed that they didnt ask me many questions.. none of them from my favourite subjects.. But as the interview was fine overall and I was able to answer all the questions I was happy.

18^th june 2019

I saw people posting that the results have been declared .. So fingers crossed I logged in and there I saw the option of Accept Seat.. I was extremely happy !!

I am thankful to everyone who helped me throughout my journey.. my parents , gate overflow .. my friends for always motivating me!!!

I gave IIITH PGEE – 2019 on 28th April,2019.

Written Exam consisted of two sections – 1. General Aptitude  2. Subject Paper (Computer Science in my case). (More information is here :https://www.iiit.ac.in/admissions/postgraduate/monsoon/syllabus)

General Aptitude section was of moderate difficulty. I was able to do most of the questions and left only 4-5 of them. Subject paper was easy to moderate. About 95% of the questions were from previous year GATE papers. While preparing for GATE, I have solved almost all previous year questions from GO PDF, so the paper seemed easy to me. I was sure that I will be shortlisted for the interview. So I started preparing for the interview right away.

I was right. I received interview call letter on 10th May, 2019. My interview date was 10th June, 2019. I had exactly a month in my hand to make sure that I don’t screw up my interview. (I will share my preparation strategy in detail later)

10th June, 2019 – The Judgment Day

I reached the IIIT Hyderabad Campus at 8:00 AM. All the candidates were standing outside a hall, staring at a list on which our names and interview panel allotted to us were mentioned. I was allotted Panel-1. I entered the hall. After a while, a professor, who was in-charge of admission process, came in. He entered and started walking across the hall barefooted (I guess he was completing his morning walk). He then told us about the selection process, research facilities and placement opportunities. He addressed all our questions regarding interview process, difference between MS and M.Tech, stipend, fellowship etc; however, he didn’t disclose details like selection criteria, cut off, result date etc. After that, we were taken for registration, and then I waited for 3 hours for my turn.

During 1st hour, my friend asked me some C programming questions on WhatsApp and I was chatting with him, discussing those questions. After that I sit back for 2 hours relaxing my mind. I saw a lot of people revising their notes, while some of them were relaxing just like me. At first, I thought of revising some important concepts and pseudo code of graph algorithms, but then I feel what I will revise right now is not going to be asked in the interview. (Spoiler Alert – I was right)

(Side Note: My friend, whom I mentioned above, got into MS programme in IIT Kanpur. You can see his interview experience here : https://gateoverflow.in/blog/8079/iit-kanpur-ms-interview-experience)

The wait was over and I, along with 2 other candidates, were taken to the interview hall. One guy went before me, and then it was my turn. I took a deep breathe and entered in. My interview went for about half an hour.

The Interview

It was a panel of four professors, out of them one was a lady professor. (I’m gonna refer to them as P1, P2, P3 and P4)

On the table there were a bunch of flowers and a bowl of eclairs (May be kept there to break our nervousness)

I greeted them with a smile (probably a fake one as I was not feeling to smile at all).

P1: What’s your name?

Me: Astitva Srivastava

P1: That’s a nice name.

Me: Thank you Sir.

P2: Have a seat. Sign the attendance sheet, and give me your certificates.

Me: *Rushing through my documents in a hurry*

P2: Give me the whole folder.

Me: *I gave the folder, thinking now they are going to analyze me completely*

P2: What’s your first preference, M.Tech or MS?

Me: Sir, MS (Smiling inside that now he’s going to ask “Why MS?”  and I prepared a really good answer for that)

P2: *To my surprise he smiled and didn’t ask “Why?”* Instead he asked, “What’s your favorite subject?”

Me: Sir, Algorithms.

P2: *Gave a gesture to P1 that you slaughter him first*

P1: *Asked me to come on white board* You are given a matrix M of integers, and a number K. Write an algorithm to find any sub-matrix of M whose elements sum up to K.

Me: *I came up with an approach but it was not efficient. I was looking for a solution involving Dynamic Programming.*

P3: OK, we need to know what you’re thinking?

Me: Sir, I am trying to come up with a dynamic programing solution. Right now I only have a brute force approach.

P1: No problem, tell me the brute force approach.

Me: Sir, for each element in matrix M, I will consider a sub-matrix starting from that element and then I will loop further to make that matrix grow cell-by-cell and keep adding the elements and stop when I get sum equals to k. 

P1:  OK, so how will you improve it further?

Me: Sir, there will be instances when part of sub-matrices will overlap. We can memoize the sum of that part and use it later to reduce the complexity of adding up the same elements again and again.

P1: Write pseudo code for that.

Me: *After struggling for a while* Sir I am not able to think of a way to perform memoization.

(I think I did right to give up so that they can ask me other questions instead of wasting the time)

P2: You didn’t studied DP?

Me: Sir I did, but there all a lot of problems. I have studied only some classical problems. Right now my mind is not going in a direction that can give me a good approach.

(I tried to be as honest with them as needed)

P1: *Smiling* OK leave DP. Devise a new algorithm to sort numbers using stack. You can take as many stacks as you want. Numbers are arriving in a stream, not stored in an array.

Me: *After thinking for a minute* Sir, I will use two stacks, say S1 and S2. Then I wrote a pseudo code somewhat like this:

                      (1) Take a number from the input stream, lets call it x.

                      (2) if (Top(S1) >= x OR S1 is empty) : Push(S1,x)

                      (3) else: y = Pop(S1)

                                  Push(S2, y)

                                  Goto (2)

                      (4) while (S2 is not empty): 

                                 z = Pop(S2)

                                 Push(S1, z)

                       (5) Repeat from (1) to (4) until all numbers are processed.

                       (6) Pop out all the elements from S1 to the output stream.

(Then I explained them the whole approach by taking an example)

P1: OK, what is the worst case complexity of this algorithm?

Me: Sir, O(n²)

P3: *trying to distract me* No no, you’re wrong it can’t be O(n²).

Me: *Explained the worst case. He seemed satisfied*

P3: The complexity you are telling about, on what factor it is based?

Me: Sir, it is based on the number of comparisons.

P3: Why we don’t consider clock cycle time, or complexity for operations like adding, multiplying etc.?

Me: Sir, we analyze the algorithms on the basis of RAM model of computation, and all of our assumptions are based on this model.

(In case you don’t know about this, take a look : https://www8.cs.umu.se/kurser/TDBA77/VT06/algorithms/BOOK/BOOK/NODE12.HTM)

P3: OK, so you’re saying that if we improve our hardware, algorithms will not improve in any way.

Me: Sir, speed of the algorithm or program will increase but complexity will remain same.

P3: Right. Well, apart from number of comparisons on what other factors the complexity of the algorithm you have written will be based on.

Me: I think only on number of comparisons.

P3: Are you sure? What about number of push and pops. Wouldn’t push and pop contribute towards complexity?

Me: *Acting over smart* Sir each push and pop will take constant time.

P3: No no, I’m talking about NUMBER OF PUSH AND POP OPERATIONS. Just tell me yes or no, will complexity depend on it or not?

Me: *Realizing my stupidity* Yes sir, it will depend on number of push and pop operations too.

P3: OK.

P2: OK, we’re done here……

Me: *Thinking, Whaaat?? Is that it?? Ask me more*

P2: *to P1* …...Sir, do you want to ask anything else or should we stop?

P1: Hmmmm...ok. I will ask some maths. What is a bijective function?

Me: Sir, the function which is both injective and surjective.

P1: You are given two sets A and B. There are ‘n’ elements in both sets. What is the number of bijective functions possible from A to B?

Me: *After thinking for a while* Sir, n! (n-factorial)

P1: No. 

(I’m still wondering at this moment while writing this post that why he said “No”)

(Before I could explain why I am getting n!, he bombarded another question)

P1: So, Astitva have you studied linear algebra?

Me: Yes Sir. (I was happy because I prepared linear algebra well)

P1: OK so tell me, what do you mean by the rank of a matrix?

Me: Sir matrices are a way to represent linear transformation, so if we take a column vector and perform linear transformation on it using a matrix M, and if the output vector lies in a K dimensional space, then we say that rank of matrix M is K.

P1: *Gave me a blank look*

Me: *I continued* If we have a matrix, then the number of linearly independent rows or columns in it is called it’s rank. We can find the rank by looking at number of non-zero rows in Row-reduced Echelon form of the matrix.

P1: *Gave me a matrix and asked its rank*

               |  1   1 |

               |  2   2 |

Me: Sir, the rank will be 1.

P1: How can you say this without reducing the matrix in Echelon form? 

Me: Sir the two vectors in the matrix are linearly dependent. So one vector can be written as linear combination of another vector and then can be reduced to zero vector.

P1: What do you mean by linearly independent vectors?

Me:  If we are given a set of vectors say v1, v2, v3 ………….…….. vN and : 

        c1.v1 + c2.v2 + c3.v3 + …………………. + cN.vN = 0, if and only if the constant ci = 0 for all i, 1<=i<=N

(I wrote the above equation on board)

……...then the given set of vectors will be linearly dependent

P1: Linearly dependent ???

Me: Sorry Sir, linearly independent.

P1: OK. That’s it from my side.

Me: *addressing the panel* Anything else you want to ask? Operating systems, Theory of Computation etc…

P4: You’re a singer? I saw your certificate.

Me: Yes Ma’am.

P4: Can computers sing?

Me: Yes Ma’am, there are some artificial intelligent systems that can sing and compose new music.

(I remembered the one I saw on YouTube)

P4: Can they sing better than humans?

Me: Not now, but I believe in near future they might.

P2: Where did you learn singing from?

Me: Sir, I’m from a musical background. My father is a classical singer and he has performed at various places. He’s been teaching me music since childhood.

P2: Okay then sing a song.

(I was like, what is happening??? Is it a technical interview or what???)

Me: Sir which song?

P2: Whatever you like.

( I asked for water as I was feeling thirsty)

( Then I sang “Afreen Afreen” song, they liked it)

P2: Have you listened to the original version?

Me: Yes Sir, by Nusrat Fateh Ali Khan.

P2: Good. OK we’re done here, you can go now. You can take eclairs if you want.

(I took two eclairs)

P2: Carefully, it’s not good for your throat.

(We both smiled at each other)

Then i took my documents from the table and came out.

As i was putting my folder inside the bag and leaving, the professor P2 came running behind me. I accidentally took attendance sheet along with my documents. 

I apologized for my mistake, to which he said “You got the attendance sheet carried away with your singing, including us.” I felt amazing.

The professors were extremely down-to-earth and supporting. They were constantly smiling so that we don’t undergo a nervous break down. It was the best interview experience till now in my life. I had a feeling that I will be selected.

I came out and instantly messaged my friend asking about question regarding bijective function. He also said n! to which I felt relaxed.

But when I came back home, I started thinking about moments during my interview where I made mistakes and my mind started to emphasize on those mistakes. Then I thought that professors were good not only with me, but with others too. I started believing that my interview was not extremely outstanding and also intakes from MS are low, so I started making up my mind for the worst case scenario.

18th June, 2019

My friend, Anuj, called me saying that someone has posted on the group that results for the interview are declared.

I checked the portal, and after a while, i got the offer letter.

I was in.

I am grateful to everyone who helped me in achieving this –  my parents, my friend Anuj, all the seniors, who supported me, gave me suggestions and clear my doubts. I know I have done hard work, but I also needed the kind of support which I got from these people.

I’m going to accomplish my dream of studying in one of the finest institutes of India.

$\text{IISc CSA MTech (Research) Interview Experience}$

$\text{Gate Score-}$ 759   $\text{Gate Rank}$- 410
$\text{Category-}$ General – EWS

$\text{Research Area –}$ Intelligent Systems
$\text{Background Subjects- }$
1. Linear Algebra 
2. Probability

Interviews were conducted over a period of 5 days (20^th  to 24^th   May). Each day there were 2 slots morning (9 am) and afternoon (2 pm). Mine was morning slot on 22^nd May.

$\text{Written test –}$ 9 to 9:30 AM
There were 10 questions of easy to moderate level. I attempted all the question out of which 7-8 were correct to my knowledge. For the rest 2 questions, I just wrote my approach.

$\text{My advice on written test-}$ 
1. Write your solutions clearly. Coming to the final answer is not that much important. They are more interested in your approach.
2. Try to attempt all the questions.

After half an hour (at 10 AM), results were out and I was the 1^st one from the intelligent system pool to get interviewed in that slot.
I was called in at 10:05 am.
The panel consisted of 3 professors.

$I_1$ –  Soumya, You have graduated from Indore Institute of Science and Technology and you have a CGPA of 7.60
$Me-$ Yes sir.

$I_1$ – Your graduation year is 2017. So what have you done in the past 2 years?
$Me-$ Sir, I had taken the decision of appearing for GATE after my B.E. Last year I got some lower rank so I again took the full-time drop for GATE. 

$I_1$- Ok Soumya, So your GATE 2019 SCORE is 759 and rank is 410.
$Me-$ Yes Sir.

$I_1$- You have applied in 3 departments. CSA is your 1^st  preference, CDS is 2^nd   and Electrical is 3^rd .
$Me-$ Yes Sir.

Then he asked me about my other interviews and other offers that were in my hand. 
$I_1$ Ok Soumya, You mentioned background subjects as linear algebra and probability. Should we start with linear algebra?
Me – Yes Sir. 

$I_1$ Which topics have you prepared in Linear Algebra?
$Me-$ System of linear equations, vector spaces, Eigen values and Eigen vectors.

$I_1$  We should start with eigenvalues and eigenvectors.
$Me-$ Sure sir

Till now 5 minutes have passed. Then they sent me to the whiteboard.

$I_1$- What are eigen vectors?
$Me-$ I wrote $Ax =  \lambda x$ on the board. Sir, x will be an eigen vector of A- if I give vector x as input here and if the output vector  $\lambda x$ comes out to be in the same direction as x.

$I_1$- Why eigen vectors are non zero?
$Me-$ Sir, they are defined as non-zero (I could have explained it properly but at that time this is what came out of my mind).

$I_1$- What are eigen values?
$Me-$ Explained it properly. 

$I_1$- Can you explain how you came to this equation $(A – \lambda I)x=0 $?
$Me-$ Explained.

$I_1$-Why determinant of this matrix  $(A – \lambda I)$ is zero?
$Me-$ Sir, As null space of this matrix, contains non zero vectors, columns of $(A – \lambda I)$ are linearly dependent. So this matrix is non-invertible hence its determinant is 0.

$I_1$- If matrix A is $nXn$ then how many eigenvalues will it have?
$Me-$ Sir, the degree of the characteristic polynomial of A is $n$. A polynomial equation of degree $n$ has $n$ roots and as roots of the characteristic polynomial are the eigenvalues of A so A will have n eigenvalues.

$I_1$- Can matrix A be rectangular?
$Me-$ No sir. We need to equate the determinant of $(A – \lambda I)$ to zero and determinant is defined for square matrices only.
(At this point, I was disappointed with my answer 😑).

$I_1$- Suppose matrix A is $3 X 3$ 
Write on the board – $A^3 = 0$ . Find the determinant of the matrix $A-3I$
Is this information is sufficient to find the determinant?

Initially, I was able to find one eigenvalue of A i.e 0 but with the help of a small hint, I got all 3 eigenvalues of A. Still, I struggled to find the determinant.
Then somehow I reached to the trace of (A- 3I).

$I_1$- How the trace of this matrix (A – 3I) is $-9?$
$Me-$ Explained.

$I_1$ - Ok. we should proceed further.

After this, I was handed over to the 2^nd  professor.

$I_2$- What is your GATE year?
$Me-$ 2019 

$I_2$- Oh, you gave the GATE recently so subjects must be fresh in your mind. 🙂
$Me-$ Yes sir 😊

$I_2$- Let's start.
I have given you a six-faced dice. You have to roll it until you get the 1^st   even number. For Ex- you rolled it for the 1^st   time and got a 3 so you rolled it again. You got 1 now. You rolled again. You got 6 this time. Now you stopped. So what is the average number of times you have to roll the dice to get an even number for the 1^st  time?
Do you understand the ques? Repeat it once, what you have to find?
$Me-$ Yes sir. Basically, I have to roll the dice until I get the 1^st   even no. I have to find the expected number of trials until I get the 1st  success.

$I_2$-– Exactly. So find it.
$Me-$ Sir I can model this situation using a geometric random variable

He stopped me in the middle. 

$I_2$-, Correct. So as you said Random Variable. First, explain it.
$Me-$ Explained.

$I_2$- What is a geometric random variable?
Explain it on the board.
I explained it properly.

$I_2$- Now model the given scenario and find the expectation. 
I found the required probabilities and derived the expectation of a geometric random variable using its memorylessness property.

When I was busy in deriving the expectation, I heard some voice from the background. When I turned they told me that I am going excellent. It boosted my confidence.🤩

$I_3$ (who remained silent all this while)- From where have you studied probability?
$Me-$ Sir- MIT OCW lectures. (I forgot the name of the professor- John Tsitsiklis 😔)

$I_3$- You have studied probability solely for GATE or this course was there in your B.E?
$Me-$ No sir. I studied it only for GATE.

$I_3$-- Ok. Complete your proof.
I completed it in the next 3 minutes 

$I_2$ asked me to explain the memorylessness property mathematically and how I used it in one of the equation.
After a few hints, I was able to explain everything. 

$I_1$- Ok Soumya, We are done with the interview.

$I_3$ – As you mentioned ML and DL as your sub areas, are you open to other areas as well?
$Me-$ Yes sir. 

The interview lasted exactly for 30 minutes. I came out exactly at 10:35 AM.
It was an amazing experience.

25^th May 2019 -the list of shortlisted candidates declared and my application number was there on the list.
5^th  June  4:07 PM – Received a mail – $\text{IISc Admissions 2019- MTech (Res) Programme Offer Letter.}$ 😍

Hello everyone, 
I am Nikhil Agrawal, a GATE Aspirant for the GATE 2019.
Rank:450
Category : General 
Gate score: 748. 
I have written a blog which contains my interview experience at IIT Madras, IIT Kanpur, IIT Delhi, IISc Bangalore (CSA),IISc Bangalore (CDS). If you get time go through this link : Interview Experience. I will be joining IISc Bangalore. If you have any doubts regarding the GATE preparation, feel free to ping me on Messenger Nikhil.
Thanks. All the best to all the future Aspirants. I wish you will get what you want in life. Dreams do come true :)

Reaching Gandhinagar

The airport nearest to IITGn is Sardar Vallabhbhai Patel International Airport in Ahmedabad. Once at airport, it takes 20-25 minutes and approximately Rs. 300 to reach the campus. Once in campus, report to Gate 2. Though they didn’t mention about providing accommodation but once I was there, they allotted me a room in their hostels with a nominal charge of Rs. 250 per day. The dining hall was next to the hostels. Dining charges were Rs. 49 for lunch and dinner, Rs. 35 for breakfast. The rooms were quite awesome, each had an air-conditioning system installed and other things unlikely to be found in an IIT hostel.

The Interview Day

They asked all the CSE students to assemble in a hall. After an orientation session about the intake and the general guidelines, they divided the students into two batches for the written test. The written test, as they were trying to hint, was focussing majorly on testing the ability of students to code.

Coding Test

The coding test was on the platform of HackerRank. The test supports almost all the languages. The use of STL and languages like Python were also available. The coding questions were:
1. We are given a keyboard. Standing on a key, it takes 0 second to press the key. 1 second to move to all the adjacent keys and 2 second to all the keys next to the adjacent keys i.e.
| 1 | 2 | 3 |
| 4 | 5 | 6 |
| 7 | 8 | 9 |
Suppose we’re standing on key 4, it takes zero second to press the key, 1 second to go on keys 1, 2, 5, 7 and 8 and 2 seconds to go on keys 3, 6 and 9. Given two strings, one containing the configuration of a keyboard and the other one denoting the sequence of number to be types, find the time the system will take to type the complete sequence.
e.g. str1 = “123456789”; str2 = “15235”
key 1 = 0s
moving on key 5 from 1 takes 1s
moving on key 2 from 5 takes 1s
moving on key 3 from 2 takes 1s
moving on key 5 from 3 takes 1s
Therefore, the answer is 4.
2. Given an array, find an index, such that the summation of all elements on the left of the index is equal to the summation of elements on the right.
e.g. arr = [1,2,3,4,6]
ans: 3 (0 based indexing)
3. Given an upper limit U, lower limit L and variable K, find a and b such that L<=a<b<=U and a^b<=k is maximum.
4. Given a sequence of numbers, for each duplicate number present in the sequence, increment it until all the elements in the sequence become unique, such that their sum is minimum as possible.
5. (I don’t remember the language of this question)
Given an adjacency matrix, find the number of connected components in that graph.
Following this, there were 15 MCQs problems based on caching, time and work, graph theory, algorithms, probability and data structures.
Out of approximately 250 students, 75 students were shortlisted for the interview. The interviews began at 2 and were done by 6 in the evening.

Interview

Q. Introduction: done
Q. Given two very big numbers, unable to be held by any variable, how will you add them?
A. Reverse them and store them in array and add each cell etc.
Q. Given two numbers, without using comparator and arithmetic operator, how will you tell whether they are equal or not?
A. XOR them inside if statement and not(!) the whole
Q. Did any projects on machine learning?
A. Explained digit recognition using back propagation algorithm with structure of perceptron models, learning rate, mean squared root error and all.
Q. Any questions from our side?
A. No Sir.
This was my interview experience at IITGn, I made it to the final admit list. Hope it helps.

GATE YEAR: 2019

GATE SCORE: 677

GATE RANK: 1046

CATEGORY: GENERAL

Written test:

Questions asked in the written test were of GATE level. The test covered almost all the GATE CS subjects, including signals and systems and aptitude. There were 2-4 questions from each subject. Really enjoyed the questions.

Interview:

Professors asked me to choose the subject. I chose data structures and algorithm. They asked the following questions.

1.  Do you know connected components? 
2. How will you find the connected components of a graph? What will be the time complexity?
3. Given two graphs A and B on the same set of vertices but with different edges. How will you find the largest connected component common to graphs A and B?
4. I want to find the shortest path between vertices ‘v’ and ‘u’ of an undirected graph. I use the single source shortest path algorithm. It may give me the wrong answer. I am okay with the error. We have all pairs shortest path algorithm which will give me the correct answer. As I am okay with error, I prefer the single source shortest path algorithm. Give me a case where this error will be very large, so I must use the all pairs shortest path algorithm.
5. What was your project? How many of you completed it?
6. Write C code to find the number of leaves in a binary tree?

The interview was a good experience. I got selected for MS. But I did not accept the offer because I got selected for Ph.D. at IIT Bombay.

https://iammriganka.quora.com/IIT-Bombay-Mumbai-or-Powai-RA-interview-scene