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My sole purpose of writing this post is that the previous interview experiences given here by our seniors have been a great help for me so I just wanted to carry forward the tradition. Moreover , take it as a token of thanks to all our seniors who have contributed to GO in any possible manner and a help for all the people who would be aiming for IITK in future. You can even read this post  just for the love of CS and because you like to do new and challenging problems.

There were 2 tests this year:

(1)Written Test (30 Marks) :

      1) 30 questions

      2) 2 hours duration

      3) We were required to choose one out of the two groups ‘Systems’ or ‘Theory’.

      4) Each question carried 1 mark each.

      5) There was no negative marking.

      6) MCQs can have multiple write answers , marks are given when all the answers are marked correctly.

      7) There were fill in the blanks and Numerical answer type questions , mostly one liners.

PS: We are not given back the question paper in IITK so I have tried to mention as many questions as I can recollect after the exam. In some of the questions I have not mentioned the exact question but just the concept the question was asked from ,an obvious reason being you cannot expect someone to remember the exact numerical values.I attempted the ‘System’ section so can’t recollect the questions from ‘Theory’section(I can add to this post if any of my friends tell me the questions in ‘Theory’section).

Q1) Address Resolution Protocol(there were 4-5 options we were required to mark all the right choices about ARP).

Q2)We were given Bandwidth,RTT,Packet Size,etc ,it was required to calculate the optimal window size.

Q3)There are two relations R1 with tuples r1 and R2 with tuples r2, r2 > r1 Minimum number of tuples in R1 Union R2.

Q4)printf -> system call or not

Q5)If we increase the pipeline depth , the time to execute a single instruction decreases.(T/F)

Q6)One program given in C language, it used string and stack, we were required to tell the correct output out of the choices given.

Q7)Given a function ,we were required to tell whether it computed a*b or a*(b+1).

Q8)Given page size and #bits in physical and logical address.We were required to calculate the size of the page table in Bytes.Each page table entry contained the translation bits,dirty bit,valid bit,etc.

Q9)There are 65 different instructions available in syatem,one instruction s1 uses a shift field based on word length and 2 registers. #registers=519. 64 bit processor .Calculate #bits used for s1.

Q10) Heap in array form given ,we were required to extractmin() and then report the resulting arrary.

Q11)Mini. #nodes in height 10 , Height balanced BST.

Q12) R1(A) PK ,R2(B) B PK references A on update cascade,R3(C) C PK references B on update cascade

R1: 1 2 3 4 5 6 7

R2: 2 4 6 7

R3: 2 4 6

Update R1 set A=A+10 where A<5;

Select sum(C) from R3;

I will add more questions here.

(2) Programming Test(30 Marks):

      1) 2 questions.

      2) 2 hours duration.

      3) Ques 1 (10 Marks) and Ques 2 (20 Marks).

      4) Language : C

      5) We were required to code on Prutor(Online web-browser based IDE for program preparation and submission developed at IITK).

       6) There were 4 visible test cases and 10 hidden test cases. 

Q1) Print the second minimum element in the given integer array.(10 Marks)

Q2)Given an input in String format. We are considering base as 15(Allowed digits : 0,1,2,…,9,a,A,b,B,….,e,E).From the input string first take out the valid base 15 digits and then print its decimal equivalent and Zero if no valid base 15 digits).(20 Marks)


Input : [email protected]


Valid base 15 digits: ace


Input : IITK


Valid base 15 digits: none

Some useful materials : Syllabus Written Test

Sample Test Written


Syllabus Programming Test

Any of my good friends who attended the IITK test and would like to suggest any corrections and additions in the questions provided here is most welcome.

posted May 15, 2018 in Interview Experience by Loyal (9,831 points)
edited May 15, 2018 by | 3,458 views


How to code Question 2 from Programming test?
2nd question had very weak test cases,

To solve it take sum =0,

Scan from left to right

for each valid digit do sum=sum*15+ digit
I've two doubt.

Scan from left to right OR right to left?

How did you arrive at this formula for sum? Please explain. I'm not able to get both queation.
Left to Right (123)(MSB to LSB)

Try with binary numbers.
I think the questions were on the easier side ( given 2hrs) & almost everyone got the programming test correct, so the admissions may be based on gate score solely after clearing the test cut off?
@Aegon Got your point.  Thanks!!

How did this formula came in your mind during exam time, especially for the "sum"?  What it random or had you practiced similar question in past?
I already knew the formula but never used it until now. Also, I had to solve few examples to recollect the formula.
Programming test level is so low. Even a first year B.Tech student can solve those questions. I didn't expect this.
Can u tell what is the cutoff to get call from iitk
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