Summary
This post details my interview experience for an SDE-2 Backend role at CoinDCX, focusing on two specific coding questions.
Full Experience
My interview for the SDE-2 Backend role at CoinDCX primarily focused on problem-solving, and I was presented with the following two data structures and algorithms questions.
Interview Questions (2)
N rooms numbered from 0 to n-1 initially only 0th room is unlocked. Rooms will have keys for any rooms. We need to find if we can visit all the rooms.
Input: [[1], [2], [3], []] output : true
We start in room 0 and pick up key 1. We then go in room 1 and pick up key 2. We then go in room 2 and pick up key 3. We then go in room 3. Since we were able to go to every room, we return true.
Input: [[1,3], [3,0,1], [2], [0]] Output: false We can't enter room with number 2 0 -> 1, 3 1 -> 0, 1, 3 2 -> 2 3 -> 0
You are given location of n number of houses on a straight line and k street lights. The street light has a power P value.
If a street light is located at location x, it will spread light from [x-P , x+P]
You need to find the minimum value of K so that we can light all the houses.
Example1:
houses[] = [1,2,3,4,5] P = 1 output = 2
Example2: houses[] = [7,2,4,6,5,9,12,11] P = 2 output = 3
Summary
I interviewed for an SDE-2 role at CoinDcx in July 2024. The interview process spanned two months, concluding with my profile being put on hold after document submission.
Full Experience
I recently interviewed for the SDE-2 position at CoinDcx in Bangalore. The entire process took about two months to complete, after which my profile was put on hold.
Round 1 (DSA - 1 hour):
This round involved two medium-level Data Structures and Algorithms questions. I focused on explaining my approach and optimizing the solutions.
Round 2 (Machine Coding - 1 hour):
I was given a machine coding problem to build a Splitwise-like application. There were also some general Java-specific questions and a discussion around database scalability concepts.
Round 3 (System Design - 1 hour):
This was a High-Level Design discussion. I was asked to design a system similar to Cricbuzz, focusing on scalability and architectural choices.
Round 4 (Hiring Manager - 1 hour):
In this round, we discussed my existing projects in detail. I also faced several behavioral questions to assess my fit with the team and company culture.
Interview Questions (2)
Design and implement a Splitwise-like application. This typically involves handling user expenses, splitting bills, and tracking balances among a group of people.
Design a High-Level Design (HLD) for a system similar to Cricbuzz. This would involve discussing components like real-time score updates, data ingestion, user profiles, notifications, scalability for live events, and overall architecture.