ONLINE TEST:
It was a 2 hour on-line test on hackerrank platform with 1 coding question (LCS), 9 MCQs related to computer science and 10 quant questions . There was no fixed time per section and people who did well both the sections were shortlisted for the face to face interviews .
750 people appeared for the test and 70 were shortlisted for the face to face round .
1st Round:
The interview started with discussion on my previous internship where i worked on the Reputation, Revenue and recommendation system .He asked me to explain the above and then asked how my recommendation system was better or worse than You-tube.Then he asked me a quant question (5 pirates have to divide money among them and highest rank pirate gets to decide) .This interview was around 25 min .
2nd round:
This was a long interview .The guy started grilling me on my CV, be sure you know every single thing on it .He asked me a lot of questions on Operating systems involving semaphores, processes running on different hosts and OOPs is a must if you have even a slight mention of c++ or java .GFG has a exhaustive collection for c++ so you should know it by heart.After he was done asking me all this he was satisfied and asked me a couple of coding questions
1)Number of islands in a grid.
2)Order matching in a continuous input stream.
3rd round:
The interview started with an abstract question : What could be the error in a code if it is falling only sometimes and not always.Then he moved on to algorithm questions .
1)Given an array of numbers corresponding to heights of people and another where i’th element corresponds to the number of people smaller than him in front of him and i had to give the order of people satisfying the constraints .
2)given a binary tree i have to return the longest increasing sub sequence .
Then he ended the interview with a quant question : Number of partitions possible of a number
n=3
1+1+1
1+2
2+1
3
ans =4
4th round :
This was the final round .It started with two a couple of straight forward questions
1) reverse a linked list
2)max average of a subset of an array (with no duplicates and with duplicates )
The she asked me some questions on statistics and probability.
1)given a random variable X=x1, x2, x3… with standard deviation (s) what is the standard deviation of X=a*x1, a*x2 …..
and asked me to prove it.
2)given a random value generator R7 which generates values from 1-7 with equal probabilities and i had to use this to make R5 which would generate values from 1-5 with equal probabilities and also had to prove the probability .
The interview ended with a question on job scheduling with constraints(some jobs have to be done before others ) .The answer was a combination of cycle finding and level-order traversal .
Total of 13 people including me were given the offer .
Some Tips:
Don’t brag in your CV if you cant deliver in the interview .This mistake was done my many and they suffered, its better to have a crisp and readable CV from which no question can surprise you.Geeks for Geeks is you best friend for preparation.
1)Finish the must do coding question section.
2)Array and DP are must so read all the 100+ articles .Questions come directly from them .
3)OOPs for c++ is more than enough on GFG so learn it
4)read as many puzzles as you can from GFG
5)prep for quant can be done from : heard on the street and 50 challenging problems in probability
At the end i would like to thank GeeksforGeeks for making my preparation less cumbersome by having such an amazing collection of resources.