CallHippo Interview Questions and Answers

Round: Test
Experience: 30 MCQ questions testing basic logical reasoning, quantitative aptitude, analytical skills.
2 coding questions --I skipped 1st that was a mistake as it was the easiest. Basic array adhoc question.
2nd-greedy algorithm based find number of platforms for a train schedule.
1 API coding on trie data structure. Functions were all there. Problem--Given a word with a letter missing...find and print possible words from the dictionary. for example--
Input- dristisofts 5
Output- drishtisofts
drisetisofts
1 debugging question-toughest of them all for me...2d-matrix find the rectangle with largest sum.
Tips: Basic Level of Questions for me. I never explicitly prepared for those. Doable.
Try both 1st and 2nd...they will be easy...C and java are only possible languages given so can't use stl.
API will be easy only lengthy...don't panic...
If you have time, you will try 4th.

Duration: 180 minutes
Total Questions: 34

Round: Test
Experience: Completely networking based problem. based on TCP protocol. packets are being dropped and changed find a way to stop it. I was able to pass all test cases. (they were having some internal problems with there test cases).
Tips: Exciting round. Use re-transmission and sequence id and hash coding. Focus on everything. Interviews will be based on these.
Duration: 60 minutes
Total Questions: 1

Round: Test
Experience: N=4. find errors and generalise for N.
Tips: Easy-peasy.
Duration: 60 minutes
Total Questions: 1

Round: Technical Interview
Experience: Lovely experience. Duration -2hours. Interviewer was a chill guy. Interview started with some light moments and we discussed about my experience with the company I did my internship with. Then there was questioning about what I did in my API coding round. I was asked to explain point by point about how I understood the problem and how I solved it. Then he started grilling me on questions based on it. One by one questions were put in some way that I had to revisit everything what I learnt in my 2nd year about transmission protocol. Everything, starting with what was the hash code used to how the window size is decided and how to reduce traffic by sending cumulative ack.
Tips: Better prepare networking before coming. Everything, every exception.

Round: Technical Interview
Experience: I was asked to tell any two of my projects. And this is where I think I got an edge over others. My resume was filled with many projects and we discussed two of my most recent projects. I had learnt about Oauth protocol and RESTful APIs so we discussed about it. Then there was this problem about a company visiting for campus recruiting wanting to conduct a test on Hackerearth + what if lights went off and students want to continue where they had left --the problem was to design a databse based on these conditions and then some questions were asked on the database I had made. Finally there was an interview scheduling problem.50 students. 3 rounds(1->P1,P2 2->P2,P3 3->P4). design an algorithm to conduct the interviews taking minimum time to process all 50 students.
Tips: Prepare your projects and DBMS as well. Be confident, build approaches to tackle problems and try finding loopholes in it and then work on those. They will be focussing more on how you will tackle a general problem and not the solution.

Round: HR Interview
Experience: Introductions with family background. Psychometric test. and then I was told to ask about the company. Interviewer was very cool.
Tips: Easy - peasy.

General Tips: Do away with any nervousness. The interviewers will be extremely friendly. Just do your best. If you know it, it isn't that hard. Hints would be given. They just test your approach and knowledge of the subject.
Skill Tips: TCP concepts and socket programming. Projects on that would be lovely.
Skills: Networking, DBMS
College Name: NIT Jalandhar
Funny Moments: The interview was held in guest rooms lying down on bed. I was even asked to take rest and sleep for an hour before interviews alongside their bed.