Hiring Guide

Top 40 .NET Coding Challenges with Solutions

Comprehensive guide covering advanced C#, ASP.NET Core, and system design challenges faced by senior developers during technical interviews.

Core Concepts
Data Structures and Algorithms
System Design
Coding and Debugging

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Core Concepts

Data Structures and Algorithms

System Design

Coding and Debugging

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Top 40 .NET Coding Challenges with Solutions

AI-Powered Technical Assessment

Core Concepts

Create a custom value object with equality comparison

Implement a custom exception handler middleware

Design a custom object pool implementation

Implement a thread-safe singleton pattern in C#

Write a custom generic collection that implements IEnumerable<T>

Implement a custom async/await operation with cancellation support

Create a custom attribute and reflection-based validator

Implement a custom middleware in ASP.NET Core

Design a generic caching decorator pattern

Implement a custom LINQ extension method for pagination

Data Structures and Algorithms

Implement an LRU Cache in C# with a capacity limit. What's the time complexity for get/put operations?

Write a C# method to find all pairs of integers in an array that sum to a given target. What's the most efficient approach?

Implement a thread-safe producer-consumer queue with a maximum capacity in C#. How would you handle concurrent access?

Design a data structure that supports O(1) Push, Pop, and GetMin operations. How would you implement it?

Implement a sliding window maximum algorithm that returns the maximum element for each window of size k in an array.

Implement a concurrent dictionary with automatic cleanup of expired entries. How would you handle thread safety?

Design a rate limiter that allows n requests per second per user. How would you implement it efficiently?

Implement a custom IEnumerable that generates Fibonacci numbers up to a specified limit. How would you make it memory efficient?

Create a generic object pool implementation that's thread-safe and supports automatic return of resources.

Implement a custom priority queue with support for updating priorities. What data structure would you use internally?

System Design

Design a scalable URL shortener service like bit.ly using .NET technologies

Design a real-time chat system using SignalR and .NET

Design a social media feed system with .NET

Design a distributed caching system using .NET

Design a job scheduling system using .NET

Design a distributed logging system using .NET

Design a rate limiting system for a .NET API

Design a notification system using .NET

Design a distributed configuration system using .NET

Design a microservices-based e-commerce system using .NET

Coding and Debugging

Write a C# method to flatten a nested list of integers into a single list.

Implement a thread-safe singleton pattern in C#.

Write a method to check if a string is a palindrome, ignoring case and non-alphanumeric characters.

Implement a custom memory cache with expiration in C#.

Create a method to find the first non-repeating character in a string.

Implement a custom attribute to validate method parameters.

Write a method to detect a cycle in a linked list.

Implement a custom exception handler attribute for logging.

Create a generic method to swap two values.

Implement a custom async lock mechanism.

Streamline Your .NET Technical Hiring

Interview Questions for Other Related Skills

Why Index.dev?

Our talent is hand-picked

We prioritize speed

We respect your budget

Top 40 .NET Coding Challenges with Solutions

AI-Powered Technical Assessment

Core Concepts

Create a custom value object with equality comparison

Implement a custom exception handler middleware

Design a custom object pool implementation

Implement a thread-safe singleton pattern in C#

Write a custom generic collection that implements IEnumerable<T>

Implement a custom async/await operation with cancellation support

Create a custom attribute and reflection-based validator

Implement a custom middleware in ASP.NET Core

Design a generic caching decorator pattern

Implement a custom LINQ extension method for pagination

Data Structures and Algorithms

Implement an LRU Cache in C# with a capacity limit. What's the time complexity for get/put operations?

Write a C# method to find all pairs of integers in an array that sum to a given target. What's the most efficient approach?

Implement a thread-safe producer-consumer queue with a maximum capacity in C#. How would you handle concurrent access?

Design a data structure that supports O(1) Push, Pop, and GetMin operations. How would you implement it?

Implement a sliding window maximum algorithm that returns the maximum element for each window of size k in an array.

Implement a concurrent dictionary with automatic cleanup of expired entries. How would you handle thread safety?

Design a rate limiter that allows n requests per second per user. How would you implement it efficiently?

Implement a custom IEnumerable that generates Fibonacci numbers up to a specified limit. How would you make it memory efficient?

Create a generic object pool implementation that's thread-safe and supports automatic return of resources.

Implement a custom priority queue with support for updating priorities. What data structure would you use internally?

System Design

Design a scalable URL shortener service like bit.ly using .NET technologies

Design a real-time chat system using SignalR and .NET

Design a social media feed system with .NET