Interview Rounds

Round 1: DSA + LLD
Q1. Asteroid Collision – Leetcode Medium
Q2. Design Chess
LLD-focused question on OOP design, piece movement, board representation, etc.

Round 2: DSA
Q1. Search in a Sorted 2D Matrix
Q2. Top K Frequent Words

Round 3: System Design
Q1. Design SplitWise
This was my first real System Design round. I fumbled a bit and couldn't present a clear and structured approach. It made me realize the importance of System Design fundamentals and practice.

Quince Preparation
These are the articles which i have collected from various website and leetcode to prepare for the interview.

DSA
1.Trapping rainwater question with running code. Asked to write the prefix approach and two pointer approach as well. *** VVVIMP -> done
2.https://www.naukri.com/code360/problems/count-distinct-element-in-every-k-size-window_920336 -> done
3.Find a target element in a sorted array -> 2024 -> done
4.Modified version of LIS
5.Sliding window.
6.From the given list of strings, find the first k most occurring strings -> 2024 -> Done
7.589. IP Address Validator -> Done
8. leetcode medium - question no - 554 brick-wall
9.Detect Cycle in a graph. Remove edge from the graph to make it acyclic -> October 2024
10.Three Sum -> 2023
11.modified Binary Search -> 2023
12.Longest substring without repeating characters -> 2021
13.Longest Palindrome substring of a given string -> 2021
14.Right View Of A Binary Tree ->https://leetcode.com/problems/binary-tree-right-side-view/
15.Max Consecutive Ones III -> https://leetcode.com/problems/max-consecutive-ones-iii/

LLD
1.BookMyShow -> Done
2.Design Chess -> Done
3.Hotel Booking -> Done
4.Design Patterns in Java -> Done
5.LLD of Google Document -> Partial Need Revision
6.Meeting Hall Scheduler -> Done
7.Flight booking system
8.Coupon management system - FR, NFR, LLD - classes, design patterns and schema, HLD
9.Snake and Ladder -> Done
10.High Level Design Of Flush Feature In Hibernate
11.High Level Design Of Rate Limiter
12.Low Level Design Of Online Book Store
13.Parking Lot - Done
14.Logging -> because mentioned in resume
15.Restaurant Management System -> Done

Other
1.async event processing questions
2.Temporal and Airflow related questions
3.MySQL types of indexes grilling
4.What is the most challenging and biggest project you have worked on?

Q1. Design Meeting Room Booking System -> June 2025 -> Done
Requirements:

• Multiple meeting rooms in a building
• Add meeting rooms with capacity
• Book a room for a time slot
• Same room can be re-booked after the slot ends
• Choose optimal room based on participant count
• Send notification after scheduling
• Add meeting to calendar of host and participants
• Handle concurrent booking (locking to prevent double booking)

Q2 -> Apr 22, 2025 -> Done
-> The interviewer was very involved, co-operative and helpful in discussion.
-> Deliverables : Completed P1 requirements within interviewer’s satisfaction.
-> Class Diagram was the main focus throughout.
-> Design a conference room booking system.
P1 : Handle case where 2 users want to book same room.
P1 : User will ask for a room for a particular timeslot.
P1 : User can ask to book a specific room as well.
P2 : A meeting can not be for more than 6 hours.

Restaurant Management System -> Done

• Discussion on Entity-Relations
• Discussion on APIs
• Discussion on SOLID and Design Patterns
• Discussion on booking API for multiple bookings
• Discussion on DB locking
• Code for the APIs

Ludo Game design
-> API design
-> Actors and usecases
-> websocket usecases in the design

Hotel Booking
-> Class Diagram + Code for Booking hotel rooms
-> Extreme focus on Concurrency.

Chess HLD
-> focus was on DB schema,
-> DB choice, B+ Tree v/s LSM Tree DBs....