InterviewTrackerLow-Level Design & Machine Coding
Design a Parking Lot System
Multi-floor parking lot supporting different vehicle types (Motorbike, Car, Truck), spot assignment algorithms, and automated ticket/fee calculation.
Design an API Rate Limiter
Configurable in-memory / distributed rate limiter with support for Token Bucket, Leaky Bucket, and Sliding Window Counter algorithms per client IP/API key.
Design Splitwise (Expense Sharing App)
Expense management app allowing users to split expenses equally, by exact amounts, or by percentages, with optimal debt simplification graph reduction.
Design an In-Memory Pub/Sub Message Broker
Asynchronous topic-based Publisher-Subscriber message queue (like a lightweight Kafka or RabbitMQ) with offset tracking, subscriber worker pools, and concurrent message broadcast.
Design an Elevator Control System
Multi-car elevator controller managing internal destination requests, external hallway hall-calls, door states, and optimal scheduling algorithms (LOOK / SCAN).
Design Tic-Tac-Toe (N x N)
Scalable N x N Tic-Tac-Toe game supporting 2 or more players with O(1) time move validation and winner detection.