Google Interview Experience For Software Engineer

Role – Software Engineer 3 (L4)

Current company – Amazon (SDE 1)

Total Experience – 2.6 years

I applied for the role through Google’s career site and after a few weeks got a call from a Google recruiter. The call lasted about 1 hour during which we discussed my current projects, and why I want to leave Amazon and join Google. Am I in practice with DSA, which platform do I use to practice DSA, and what is my score? She briefed me about the interview process and asked about my availability for the Technical Phone Screening round. After a few hours of this conversation, I got an email with meets invite for a telephonic screening round.

During the call, the recruiter asked me which language I would be using in the interviews. I said Java. Don’t know why she sounds surprised.

Telephonic Screening Round

It was a 45-minute round. 3-4 minutes for introduction and then directly jumping to the question.

• There is an array provided which has either negative or positive numbers, denoting the transactions. Have to find out the maximum transactions that can happen before the balance reaches zero, we can start with anywhere in the array.
  I got in a few seconds that this was Kadane’s algorithm problem but I gave the interviewer brute brute-force solution. He asked me to optimize it then I gave him Kadane’s solution. I missed handling one edge case and he gave me a hint. I got the hint and covered that edge case as well.
• In the above question, if we have multiple sub-arrays giving the maximum answer, return the last one. I gave him a brute-force solution of finding each answer and then checking for the latest one. He asked me to optimize. It took me around 5-10 minutes to optimize but I was not able to write the code as there was no time left but I orally explained to him how I would achieve the optimal solution.

After 1 hour of the interview, I got a call from the recruiter. She had a very detailed summary of the interview and she said I will be proceeding to the next rounds. She explained there would be 4 rounds, 3 technical and one Googliness. In a few days, my all rounds were scheduled.

Technical Interview 1 :

• There is a door, and on both sides, people are in a queue to go to the other side of the door. But there are certain conditions like: At even sec only people can come in, at odd seconds only people can go out. For the first second if there are people at both sides then a person will go out. if the last person has gone in and there is no person to go out then only after 2 seconds next person can go in. It will take one second for each person to go in/out.
• The question seems confusing but I think the interviewer wants to test implementation skills rather than logical skills as the solution can be created just using if-else statements. I was able to give the solution orally in 5 minutes but when the interviewer asked me to implement. It took most of my time. I was not able to complete the implementation and I ran out of time.

Result – 50/50 nor hire nor no-hire

Technical Interview 2 :

• Suppose there is a 2d metric and you are at any one cell. There is a cheese in another cell and some cells are water, you can not cross water and you have to reach the cheese. There is a cat in one cell and you have to choose the path in which the distance from the cat should be maximum.
  I was able to identify this as a binary search problem like aggressive cows with a twist of classic 2d array DP. I was able to solve and implement the code in 15-20 minutes. The interviewer was impressed. She said she was not expecting anyone to solve this in 20 minutes and she took around 5 minutes to find a 2nd question for me.
• There is an array of integers. The value at any position defines the number of smaller numbers in an original array to the right of it. for example, if the 2nd last number in the given array is 1 that means in the original array there is one number smaller than it in its right. Find the original array.
• Firstly this question seems confusing. It took me 5 minutes to understand the problem itself but I was able to recognize this is a permutation problem and can be solved through recursion. I gave her a recursive solution, and she asked me to optimise, I was thinking about the states to create DP but then I ran out of time.

Result – Hire

Technical Interview 3 :

The interviewer was from Russia and I was not able to clearly understand his accent!

• Given a number n, Find the sum of the factorials from (1 to n). Very easy I did it in 2 minutes. He asked me how I was going to handle a very large number. I said String but he was not satisfied, I said I would use mod operation to always convert a long number into shorter and then recalculate it but he was not satisfied. I said I will use BigInteger which is capable of handling any large number in Java. He said okay, let’s move to the next question.
• There are n meetings to be scheduled and there is a list of meeting rooms with available slots. We have to maximise the duration of the meetings and set them in the available slots. Meetings can not overlap with other rooms.
  I solved this using binary search by maximising the duration of meetings and putting it in the slots. The time complexity was nlogn of my solution. As I completed the implementation, the interviewer said the time was up.

I checked and found out this question can be solved in O(n).

Result – No Hire

Googliness round

This round was totally about leadership principles and behavioural questions. Some situation-based questions. Honestly speaking it was nothing compared to what I was thinking. There were no technical or project discussions.

Result – Hire
Final Result – No Hire
It was a wonderful experience, the recruiter was very professional and I was impressed by the level of questions asked in the Google interview. This has encouraged me to prepare more and apply again.