Interviewer :--- Hi , Introduce yourself.

Introduced name , GS-698, cat-EWS, Btech in biotech From NIT Durgapur

There was silence for 30 secs after I told biotech

Int:--

Why MTech?

Me:- want to work with computer vision in future and primarily i want a cs degree to be eligible for jobs

Int:- subjects u want us to ask from?

Me:-- LA & prob, OS, DS

Int 1:-- have u heard of linear regression? (me → yes) then tell me if y=A theta ; then theta = A^-1 * y ? Am i right?

Me :-- confused with few terms he used in terms of linear regression(like feature vectors and all ). I said as per linear algebra yes

He:- always?

me:- no, if A is non singular then possible,

he:--- if that's a non square matrix?

me:-- no still not possible

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He went somewhere, interviewer 2 comes, “ it seems u are having difficulties I will go for very basic questions.”

Int 2:-- A min heap is there .. TC read to get the max element ..

Me:-- O(n)

He:- how?

Me:-- max element is present at the lowermost layer… so we can traverse the min heap using in/pre/post order and just get the maximum

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He:- how to write a program for returning 1 if it has A[i]= i or else -1 , if the array nos, are DISTINCT Integers and sorted

me: – traverse it and check the condition

He:--- TC ??

Me:-- O(n)

He :--- optimize it (Sorry sir,dont know, after thinking a few moments [i missed the word ‘sorted’ in tension])

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He:- Prove that for a graph at least 2 vertexes will have same degree.

Me:- Told

he:- ok

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He:-- prove that a DAG has at least one node of indegree 0

Me:- tried but can't do

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He :-- there is an array with n elements of which k are distinct. Sort them and prove that there TC for this prog is n log k

Me :---- tried but can't do , said sorry sir

Ok lets try OS as u said,

Me :-- ok Sir

He:-- page size if made smaller what's the advantage and disadvantage

Me:-

the advantage is in an average there is a wastage of page size /2 so if lesser the page size lesser is the wastage

he:- ok and disadv?

me:- disadvantage is lesser the size for occurrence of page fault and thrashing.

he:-- all that's fine, but i am looking for some other points

me— blank

he :-- it has some effects on page table?

me :-- yes sir the page table size will increase

he :-- hows that a disadvantage

me:-- sir Page table is an extra burden to the MAIN MEMORY hence , increasing its size is increasing the burden.

he:--- ok, i am done , ask if u have any questions

me:-- no questions, thanks for making me eligible to for the interview

he:-- don't worry, being from biotech, u were good...thanks

me:-- thank u

So this was the scene, it didn't go up to the mark, lets see.

Whatever be the result i am pleased with their patience and gesture of the profs , they were very good and tried to pacify me as much they could

There was silence for 30 secs after I told biotech