Coding Challenge Problems with Solutions

Practice coding challenges with worked solutions and explanations, covering the problem-solving patterns that come up most in interviews.

Sharpen your skills with curated coding challenges from beginner to advanced

How to Approach Coding Challenges

Algorithm & Problem-Solving Glossary

Ready to Start Coding?

Open the Try It Yourself editor, pick a challenge, and start solving. The best way to learn is by doing!

String Manipulation

Master text processing — one of the most common tasks in real-world programming. From reversing strings to parsing complex patterns, these challenges build a foundation you'll use every day.

Array & List Challenges

Arrays are the backbone of data structures. These challenges teach you to think about iteration, sorting, searching, and efficient data access patterns.

Math & Logic

Sharpen your logical thinking with mathematical challenges. These problems train you to break complex problems into smaller, solvable steps — a core programming skill.

Data Structures

Understanding data structures is what separates a beginner from an intermediate developer. Build these from scratch to truly understand how they work under the hood.

Algorithm Challenges

Algorithms are the recipes of programming. Master sorting, searching, and optimization techniques that form the basis of efficient software engineering.

Web & API Challenges

Put your skills into practice with real-world web development challenges. These tasks mirror what professional developers do every day.

Understand Before You Code

Read the problem twice. Write out examples by hand. Identify inputs, outputs, and edge cases before touching your keyboard.

Break It Down

Decompose complex problems into smaller sub-problems. Solve each piece independently, then combine them into a full solution.

Start Simple, Then Optimize

Get a working brute-force solution first. Once it works, analyze its time and space complexity, then look for ways to improve.

Practice Consistently

Solving one problem a day is better than cramming ten in one session. Consistency builds pattern recognition over time.

Time Complexity

Space Complexity

Big O Notation

Brute Force

Edge Case

Recursion

Sliding Window

Divide and Conquer

Dynamic Programming

Greedy Algorithm