Groupon Interview Experience – SDE II for Experienced

Hackerrank: (You have to finish the below two questions in 75 minutes)
1. Don’t remember the exact problem. It is a DP problem similar to this.

https://www.geeksforgeeks.org/maximum-sum-such-that-no-two-elements-are-adjacent/

2. Again, don’t remember the problem. Below is the solution I gave.

public static int minimumMoves(List<Integer> a, List<Integer> m) {

// Write your code here

int i, length, tempCount, mainCount;

length = a.size();

tempCount = 0;

mainCount = 0;

for(i = 0; i< length; i++) {

int num1 = a.get(i);

int num2 = m.get(i);

tempCount = 0;

while(num1 > 0 && num2 > 0) {

tempCount = tempCount + Math.abs(num1%10 – num2%10);

num1 = num1 / 10;

num2 = num2 / 10;

}

mainCount = mainCount + tempCount;

}

return mainCount;

}

Below rounds are in person.

PS / DS / Algo:
1. Given a n*m matrix with gems(positive numbers) and poison(negative numbers), find the maximum gems that can be collected while moving from 0, 0 to n, m. You can move in either east or south or south east directions.
2. You have a stream of numbers. When a new number comes, sort the array and insert it. (That is the existing numbers should be sorted and the new number should be inserted in this in sorted order)
3. You have 900 GB of integers in the disk and 100 GB of RAM. You have to sort them in the RAM and store the sorted order in disk. How to do that? (No coding for this, just discussion of the solution)

System Design / Architecture:

Below are the questions asked. He asked me questions on what I’ve worked already and some scenario questions.
1. What are the types of heap memory?
2. Difference between synchronized and static synchronized function.
3. What happens internally when a method is synchronized?
4. Have you worked on AWS, NoSQL, Caching etc?
5. There are multiple nodes. How do you connect a node to the database?
6. Have you ever fine tuned a SQL query? What is the procedure for it and how do you do it?
7. Given a piece of code which has a HashMap. Two threads are trying to update the value for the same key in the HashMap. What happens? If we use a ConcurrentHashMap, what happens then?
8. How do you monitor / analyze the logs in production?
9. In a multinode system where some node is handling many requests, how is the request routing to other nodes happen?
10. There are some insert to the table from the code. One insert statement is failing. You want to insert either all or none. How do you handle this programatically? If you are gonna rollback to the previous checkpoint, how do you do that in the code?
11. Have you ever fixed a production issue which is not a code issue or data issue but because of resource issue? Eg: Such as have you ever changed any GC parameters etc?

Hiring manager:
1. Tell about yourself and your projects
2. Design BookMyShow
3. What is your weakness?
4. What is a constructive feedback given by your current manager and what is an area of improvement.
5. Describe yourself in one word.
6. Who decides the roadmap in your org and how is that decided?
7. What is the process followed? Are you an individual contributor or are you part of a team which works on a single project?

Bar raiser (Director round):
1. Tell about yourself and your projects
2. What is your learning and what have you been doing for the past 6 months?
3. Tell me a situation where you’ve gone out of your way to help with the project
4. What is the feedback given by your manager about you? (Both positive and negative)
5. Do you have teams in US whom you’ve to coordinate with? If so, how do you do that?
6. How do you approach a production issue?
7. How important do you think is the team collaboration? What will be the emotion when you leave the existing team?