Hashedin by Deloitte Interview Experience for SDE-1 | On-Campus (Internship + FTE)

Preparation Tips: GFG Top Interview Questions https://www.geeksforgeeks.org/must-do-coding-questions-for-companies-like-amazon-microsoft-adobe/, solve all Dynamic Programming Problems. It’s the favorite of all the companies these days. If you solve all these questions available on the page, no one can stop you from clearing the interview, if you have a good grasp of concepts. I have prepared from multiple resources like GFG and other YouTube Channels. 

Operating System, Database Management System  (SQL this is really important these days), in my case they didn’t ask Computer Networks, There are lots of free resources available on YouTube, you can prepare from that.

For Coding Rounds : Give contests regularly no matter what, I am 2 star at CodeChef. The thing is that it will give you confidence, give all contests on Leetcode, Codeforces, CodeChef, just for practice and confidence.

Now the Main Part: There is 1 coding round, 2 Technical rounds, and 1 HR round.

Coding Round:

You are given a sequence as an array, you have to return the length of the longest increasing decreasing sequence that you can make, duplicates are not allowed

Example : 6 7 6 6 1 1 1 2 2 3 4 7 5
Output: 10       //1 2 3 4 5 6 7 6 2 1  “max element counted only once, and rest elements at max 2, observation-based questions can be solved using hashmap”

You are given an element represented as an array, you have to multiply it with V, where V is some number. V is 9 I guess. (You can use the method that you used in school)

The question is similar to this, https://www.geeksforgeeks.org/count-of-different-numbers-divisible-by-3-that-can-be-obtained-by-changing-at-most-one-digit/

We have to write the most optimal code, for every question, there are hidden test cases as well, so think well before submitting, otherwise, if you’re not qualified then you blame everyone for the same.

Note: Comment and document your code well.

Those who solved all three questions proceeded to technical round 1.

Technical Round – 1:

1. The first Question was this https://www.geeksforgeeks.org/problems/minimum-deletitions1648/1
2. The second question was this https://www.geeksforgeeks.org/minimum-number-of-jumps-to-reach-end-of-a-given-array/

He shared the link and told me to submit it on the GFG Platform. Luckily I am able to solve it, all test cases passed. Then, he asked me some questions from Operating System and Database Management system.  

ACID Properties, Thrashing, I didn’t remember all, but the notes you prepared or for sheets available, these days are good enough, the questions are from them as well. In my case, they didn’t ask Computer Networks.

I did well and qualified this round.

Technical Round – 2: It is divided into 3 parts  

1. Java
2. Programming
3. Design

Java-related questions (He asked me for language preference at the beginning)

1. Garbage Collection in Java, which algorithm is used for Garbage Collection
2. Function Programming in Java? Does it support higher-order functions?
3. Singleton Objects
4. Composition in OOPS
5. Aggregation in OOPS
6. Spring Boot
7. How would you go about building API’s in Java
8. JVM

Programming:

Write a function to write nth Fibonacci Number in O(N) Time Complexity in O(1) Space.

He thought I’ll write recursive, then memorize the solution, then write its bottom-up and then optimize the space as well, I directly wrote the final solution, this is the easiest problem one can get.

How would you go about solving Rubik’s Cube? (Only Approach)

1. Solve for steps needed to reach the solved state of the cube
2. Data Structure you will use
3. Algorithmic Paradigm
4. Time Complexity

Design: How would you go about Designing Instagram?

1. What would your DB Scheme look like:
   1. What would your query look like for fetching all recent photos of the given user?
   2. How would you write the query for fetching all photos, for a user feed?

I wrote the query for the same, in DB he asked me what are the schemas you gone make, I told him user schema and posts schema, and the attributes, the primary key and foreign key all that stuff.

He told you did well, in the end, when I asked for feedback

HR Round: This round lasts for 30 minutes.

1. He asked me about my family background.
2. Why Hashedin?
3. Tell me your 3 strengths, also tell me about the situation when you showed them.
4. Why should we hire you?

HR is very friendly, and the round went really well.

After 2-3 hours, I got a mail that I am selected. I am the only one who got selected from my campus. This seems easy, it’s your luck, remember luck happens to those, who make it happen.

All the best, and good luck.

Thanks for reading.