A curated collection of low-level design (LLD) problems implemented in Java. Each folder contains a self-contained project with its own README and codebase.
| Problem Name | Description | Link |
|---|---|---|
| Snake And Ladder | Simulates the classic board game. Players roll dice, climb ladders, and avoid snakes. | ReadMe |
| Splitwise | Expense management and splitting among a group. | ReadMe |
| Parking Lot | Design a parking lot system supporting multiple vehicle types and floors. | ReadMe |
| Trello App (Project Tracker) | Implements a Trello/Jira-like board for project and task management. | ReadMe |
| Tick Tack Toe | Terminal-based implementation of the classic game with extensible grid and player types. | ReadMe |
| BookMyShow (Ticket Booking) | Scalable movie ticket booking system with seat selection and real-time availability. | ReadMe |
| ATM System | Low-level design of an ATM with authentication, transactions, and error handling. | ReadMe |
| Multi-Level Cache | Implements a multi-level cache with LRU eviction and configurable hierarchy. | ReadMe |
| Distributed Cache | Design a distributed, highly available cache system similar to Redis/Memcached. | ReadMe |
| File System | In-memory file system supporting folders, files, and basic operations. | ReadMe |
| Library Management System | Manages books, users, and borrowing operations for a library. | ReadMe |
| CrickBuzz (Cricket Scorecard) | Simulates a cricket match scorecard with ball-by-ball updates. | ReadMe |
| High Frequency Trading System | Design of a trading system for real-time market data and order management. | ReadMe |
| Online Food Ordering System | Order management across multiple restaurants with capacity and menu handling. | ReadMe |
| FlipMed Appointment System | Medical appointment booking with slot management and waitlist. | ReadMe |
| Elevator System | Design of a building elevator system with request handling and dispatching. | ReadMe |
| Car Rental Service | Car rental management with booking, availability, and pricing. | ReadMe |
| Bus Booking Service (RedBus-like) | Bus ticket booking system with seat selection and route management. | ReadMe |
| Company-Specific Problems | Specialized LLD problems asked in interviews at top tech companies. | ReadMe |
| Design Patterns | Reference implementations and explanations of common design patterns. | ReadMe |
| Distributed Logging System | Simple distriubted logging system using java | ReadMe |
| Browser History Simulator | Simple browser history implemted using double linked list | ReadMe |
For more details on each problem, visit the linked README/problem statement in the respective folder.