Top 10 Sites for Programming Exercises in 2023

LeetCode/HacketRank/Codewars/TopCoder/CodeChef/Project Euler/Exercism/SPOJ/CodingBat/AtCoder.  Who doesn’t love solving programming problems?


I feel like they just make you a better developer and software engineer.  It’s great to just have a chance to practice, and getting good at these can really help with job interviews.   Whether you are brand new, or extra experienced, it’s always fun to work on programming exercises.  There have been a lot of subtle skills, like fast problem solving, and recognizing already invented algorithms, that I have learned from exercises like these.

A quick GPT search suggests the following sites:

    1. LeetCode: This popular platform offers hundreds of coding challenges across various difficulty levels. LeetCode is highly regarded for its extensive collection of problems and is often used by software engineers preparing for technical interviews. It also provides a vast number of algorithm questions, helping users to master data structures and algorithms.
    2. HackerRank: HackerRank is another well-known platform that provides coding challenges and competitions in various domains, such as algorithms, data structures, artificial intelligence, and databases. It’s an excellent place for programmers to learn and practice different programming skills and test their abilities against others in timed competitions.
    3. Codewars: Codewars offers a unique approach to coding challenges. Users earn ranks and honor by solving problems and completing Kata, which are small coding challenges created by the community. It’s a fun and gamified way to improve coding skills while working on real-world problems.
    4. TopCoder: TopCoder is one of the oldest and most respected competitive programming platforms, hosting coding challenges and Single Round Matches (SRMs) for a worldwide community. It also offers regular competitions in various categories, such as algorithm, data science, and development.
    5. CodeChef: CodeChef is a global competitive programming platform that provides coding challenges and contests in various domains. With a vast array of practice problems and monthly contests, CodeChef is a great resource for programmers looking to enhance their skills and compete with other developers worldwide.
    6. Project Euler: Project Euler is a collection of challenging math-based programming problems. The problems on this website often require a combination of mathematical insight and programming skills, making it an excellent resource for those interested in both fields.
    7. Exercism: Exercism is a platform that offers coding exercises for more than 50 programming languages. It encourages mentorship and collaboration, as users can submit solutions and receive feedback from experienced programmers.
    8. Sphere Online Judge (SPOJ): SPOJ is a powerful competitive programming platform that offers a vast collection of algorithmic challenges. It supports over 40 programming languages and provides users with a lot of flexibility in their choice of tools and techniques.
    9. CodingBat: CodingBat is a free website that provides coding challenges in Java and Python. It is an excellent resource for beginners looking to practice their skills in these languages and understand essential programming concepts.
    10. AtCoder: AtCoder is a Japanese competitive programming platform that offers regular contests and a collection of practice problems. The platform is known for its well-designed problems and active community, making it an excellent choice for programmers of all skill levels.


Try them out! Or just make up some programming problems and try with your friends.  For example, can you write a program that can tell if another program will halt?  Or can you probe that it’s impossible to do? 


Good luck!