Perfios Campus Placement Experience

Perfios had recently come to our college to recruit interns and full time employees for the role of Software Developers. We had to go to their office for the process.

Round 1:
First we had an Aptitude round, which was of intermediate level.
After that they gave a presentation about the company.
Everyone who had taken the Aptitude test had to take a coding test.
The coding test was written and had 4 questions.
1. rotate the characters of a String by k times
if the input is abzi and k is 2
The string becomes cdbk

2. Count ways to reach the nth stair( Count ways to reach the n’th stair – GeeksforGeeks)

3. Add two numbers represented by linked lists(Add two numbers represented by linked lists | Set 1 – GeeksforGeeks)

4. minimum length unsorted subarray(Find the Minimum length Unsorted Subarray, sorting which makes the complete array sorted – GeeksforGeeks)

After this they shortlisted 11 candidates for the interview process

Anybody who solved almost 3 questions were through

Round 2:

This was a face to face technical interview.

They initially ask us as to why we got a problem wrong or didn’t solve in our coding test if there was a mistake or if we haven’t done a problem.

We must write the code.

Next he asked what my recent projects were and to explain them, I had done a project on Networks, so he asked me questions on Networks.

He asked me the OSI Model, and the use of every layer, particularly of the functions of transport layer.

TCP vs UDP.

Next he went on to ask a variation of this problem(https://www.geeksforgeeks.org/sort-an-array-of-0s-1s-and-2s/)

He then asked me if I knew Stacks, and asked me its uses

He asked me to design a special stack data structure to find the minimum and maximum element, I gave him the approach with extra space(https://www.geeksforgeeks.org/design-and-implement-special-stack-data-structure/)

Next he asked me a database query to find the second largest element in a table

Around 8 were shortlisted after this round.

Round 3:

This was a managerial+technical interview.

He asked me if I knew Hashmaps in java, and asked me to find the maximum possible words which can be formed from characters in string.

Next he asked me write code for a system where if given an amount we should return the minimum number of notes of different denominations to the user.

Around 2 people were eliminated in this round.

Round 4:

This was a HR round.

They asked about family background and other interests.

Basically they want to know if you are passionate and enthusiastic.

At the end 5 of us were given an offer for internship+full time