Exercises

Browse All Exercises

Search and filter across the entire exercise library.

97 exercises

mediumTypeScript
Next.js API Route - Contact Form Validation
Build a Next.js-style API route handler function that validates contact form submissions and returns appropriate HTTP re...
nextjsapi-routesvalidation+6
mediumTypeScript
Virtual List Component for Large Datasets
Build a virtualized list component that efficiently handles rendering thousands of items by only rendering visible items...
virtualizationperformancescrolling+6
mediumPython
Token Bucket Rate Limiter
Implement a rate limiter using the token bucket algorithm. The token bucket is a classic algorithm for rate limiting tha...
algorithmsrate-limitingtoken-bucket+5
hardPython
DAG Task Scheduler
Build a task scheduler that executes tasks while respecting their dependencies using a Directed Acyclic Graph (DAG). Yo...
graph-algorithmstopological-sortdag+5
mediumTypeScript
User Data Fetcher with State Management
Build a data fetching component that loads users from a mock API and manages all possible states. ## Requirements Impl...
asyncstate-managementerror-handling+6
easyTypeScript
React Counter Component with useState
Create a Counter component using React's `useState` hook that manages a count value and provides user interaction button...
reacthooksuseState+3
mediumTypeScript
Todo List State Management
# Todo List Component Implement a `TodoList` class that manages todo items with full CRUD functionality. Each todo shou...
typescriptstate-managementcrud+5
mediumPython
In-Memory Key-Value Store with TTL
# In-Memory Key-Value Store with TTL Implement a key-value store that supports automatic expiration of keys after a spe...
data-structurescachingtime-to-live+5
easyPython
URL Shortener with Base62 Encoding
Build a URL shortener class that can encode long URLs into short codes and decode them back. Implement a `URLShortener`...
hash-mapbase62encoding+5
mediumPython
Consistent Hashing Ring
# Consistent Hashing Ring Implement a consistent hashing ring data structure that distributes keys across nodes while m...
hashingdistributed-systemsdata-structures+4
mediumPython
Build a Pub/Sub Message Broker
Create a `MessageBroker` class that implements the publish-subscribe pattern. This messaging system allows components to...
pub-subobserver-patternmessaging+5
mediumSQL
Relational Division: Customers Who Ordered All Products in a Category
# Find Customers Who Ordered Every Product in a Category Write a SQL query that finds customers who have ordered **ever...
sqlrelational-divisionjoins+5
PreviousPage 3 of 9Next