OLX Security Engineer Interview Questions and Answers

Round: Test
Experience: There were around 10 MCQ questions and 3 coding questions. Quantitative ability was tested in MCQs and programming and algorithmic skills were tested in coding questions.
Tips: Don’t try to over-optimize your algorithms if time doesn’t permit. First write a pretty decent algorithm. You will get through the written test. After that, try to optimize your algorithm only if time permits.
Total Questions: 13

Round: Technical Interview
Experience: Questions on basic data structures of Computer Science. Basic tree algorithms with coding. Some analytical questions.
Tips: In all the interviews, try to be as confident as possible. Sometimes they will just see your confidence and they will take you through that round. So be confident and be happy.

Skill Tips: CGPA > 7.5, decent algorithmic skills and coding skills, good analytical skills. No computer science in-depth knowledge is required. They didn’t consider any extra-academic involvement. Maths ability such as probability was required. Quantitative ability was required in Written Test. Proficiency with any programming language was enough. You should be able to explain your BTP project in full details. For internship, apart from project related technical knowledge, you should have an idea of the business relevance of the project. Try to prepare with people giving CAT. This will help enormously.
Skills: Coding
College Name: IIT KHARAGPUR

Round: Technical Interview
Experience: The interview mainly focused on coding of which I had very less preparation and was out of my curriculum. I also interviewed with Samsung and got selected there.

College Name: IIT KANPUR

Round: Resume Shortlist
Experience: I had a standard resume for this company as per our institute placement cell norms.For any software company in general, do mention all software projects you have done and languages/software packages you know.

Round: Test
Experience: The first round of the selection process was a written test which comprised of two sections. The first section had aptitude based/puzzle based problems. Questions were tricky and didn’t require any calculation. Some of the questions were
(1) Form all numbers from 1 to 10 using four 4’s and the basic arithmetic operations +,–  ,* and /(2) Pick the odd one out from a given series.(3) Complete the series (a series with the starting alphabet of days in a week was given).(4) How many knights can you place on a standard chess board so that no piece can attack any other piece?Subjective answers had to be given with proper explanation for the same.The second section was based on C/C++ programming. There were three questions. The first one required the candidate to write the output of a given program. The next question was based on simple if-else statements while the last question was based on circular queues. All questions in this section were easy if the candidate has decent enough programming skills.

Total time for both the sections was 1 hour. There was no marking scheme and short listing was done based on the overall response of the candidate. Some particular questions or parts of questions, however, were considered more important by the company, and candidates answering those questions and a few others correctly, were shortlisted for the next round.

Round: HR Interview
Experience: The first round was a 1 to 1 interview wherein the interviewer tried to put me under pressure by pointing out mistakes in my answers to written test and making me solve the questions which I had not attempted in the written test. He also asked me about my family background, why I think I should be shortlisted for the next round etc.

Round: Technical Interview
Experience: The next interview was a purely technical interview. The interviewer asked me about the programming languages I had worked on. No question was asked from languages other than those I mentioned. There were some standard questions about data structures and their implementation using C++. As I had worked on a couple of websites, the interviewer asked me questions related to HTML/CSS/PHP/MySQL/JavaScript. I was also asked to show one of the websites I had designed on the internet and the interviewer asked me a few questions about it. Except for a few, questions were very basic and easy for someone with good programming skills.

Round: HR Interview
Experience: The final interview mostly had HR questions. The interviewer talked at length about my interest in sports, my favourite sportsman and why. He also questioned me regarding the websites I had worked on, other extracurricular activities and what did I learn from them, what do I know about eBay and how would I be able to contribute to it if I am selected.
Tips: Revise programming concepts. Do not panic even if the interviewer tries to put you under pressure.

College Name: IIT ROORKEE
Motivation: eBay is a renowned company. I didn't have much idea about the job profile on offer. However I did know that it was in the field of website and software development. I also found a lot of information about the company through the company’s Wikipedia page.

College Name: IIT ROORKEE

Round: Resume Shortlist
Experience: I had a standard resume for this company as per our institute placement cell norms. eBay interviewers were not much concerned about the resume but they would surely browse through it and ask you questions from it. So it’s better to write genuine stuff rather than bluffing about things you have not actually done.

Round: Test
Experience: The first round was the written test. The test consisted of two sections one dedicated to the programming questions and the other to the logical reasoning questions. The paper was tough or so to say very unique. The programming questions were based on stacks and queues. One question was asked on circular queue. In logical section one of the questions that I remember was to derive numbers from 1 to 10 using only 4 four’s with the help of any of the mathematical operations. Other logical questions were more or less similar to this. There was also a general aptitude section which was comparatively simpler.

Round: HR Interview
Experience: This round was an H.R. interview round.He reviewed my resume and asked me some questions based on that. It was sort of a stress round as the interviewer was pushing me for answers.

Round: Technical Interview
Experience: In this they tested my programming and data structure knowledge. In data structure I was asked that, if there was a duplicate entry in a given link list then how would I find it. He also asked about the virtual functions and exception handling. He also inquired about the project that I had worked upon – I walked of a coding project in which I had used some unconventional algorithms.
Tips: Good knowledge of data structure and database management may prove helpful. They are more concerned about your knowledge. If you are good at web coding then it is always an added advantage.

College Name: IIT ROORKEE

Round: Test
Experience: Aptitude was quite easy they just asked us basic questions from Math,logical reasoning and english
Tips: Just think well before u do..
Duration: 1 hour 30 minutes
Total Questions: 40

Round: Behavioural Interview
Experience: It was face to face .. the interviewee asked questions from our resume... Since I m from computer science background they asked some technical questions..

Tips: Beware filling ur resume.. they will ask every stuff that you have in resume

Round: Technical Interview
Experience: Discussion about my project that i vr done in my final year.they asked me what was my role in my project

College Name: Sri ganesh college of engineering and technology

Round: Test
Experience: there were 20 MCQ which were on ds , networks and basic coding followed by 2 coding questions.
1) print all the distinct substrings of a given string in lexicographical order
2) find the max i-j value in the given array of 0's and 1's such that there are equal number of zeros and ones, where i is the starting index and j is the ending index of the array.
Tips: make sure that you pass atleast half the test cases for both the question.
Duration: 90 minutes
Total Questions: 22

Round: Technical Interview
Experience: 1) i printed left view then leaves and right view using three level order traversals . he asked me to use one traversal only, then i told him the approach and wrote the working code.
2) told him the approach and coded it.
Tips: look at corner cases properly. the interviewers were friendly, so i felt relaxed.

Round: Technical Interview
Experience: 1) i told him a recursive O(2^n) solution, optimised it to O(n^2). he told me to optimise further. Then i finally came up with O(n) solution after 5 min and he was satisfied . i coded it. he was satisfied finally :D .
2) came up with the approach immediately and coded it. he was satisfied.
Tips: he was very particular about corner cases and he checked the code througly tested it on some cases to ensure it was working.

General Tips: be cool. interviewers were friendly. tell them what you are thinking and be clear with the question before answering to avoid wasteage of time.
Skill Tips: solve problems from codechef, spoj and codeforces. solve interview questions from geeksforgeeks and careercup.
Skills: the way you think, coding skills and knowledge on data structures.
Duration: 3
College Name: IIT Roorkee
Motivation: some good seniors got intern, so i was inspired.
Funny Moments: on the interview day a person came into the conference room to call me for interview, i didnt thought he was interviewer. he was very simple, but intelligent and at last i felt like asking him to ask me one more coding question as it was fun solving questions infront of him, but i didnt do that as i was frightened if i would not be able to answer it would be a negative remark :P .

Round: Problem Statement
Experience: coding and submission before face to face interview shortlisting
Tips: practice coding ,coding is key to success for SE

Round: Resume Shortlist
Experience: based on marks ,I was called for F2F
Tips: the ppt was to be submitted explaining the approach

Round: Technical Interview
Experience: a lot of brain storming
Tips: understands the nitty gritty of the structs and algos

Round: Technical Interview
Experience: exact code was to be written instead of pseudo code
Tips: get hold of DS,Algos