Towards Data Science
Apr 11, 2020
Top 25 websites for coding challenge and competition [Updated for 2021]
Here is my list of the best websites for coding challenges and competitions to practice coding..
I t’s the year 2020, the end of a decade, the start of another. Throughout the 10 years of human thriving and flourishing on Earth, we have made phenomenal breakthroughs in Science and Technology.
Just to name a few: the first landing on Mars with the Curiosity Rover (2012), detecting gravitational waves from deep space (2015), the introduction of a gene-editing superpower — CRISPR (2018), “taking” the first-ever picture of a black hole with the Event Horizon Telescope (2019).
The rise of AI
By the same vein, The most significant breakthrough in the 2010s is the rise of Artificial Intelligence, or more well known as A.I. With AI, science fiction comes to life.
Machine Learning gives machines the ability to learn and Deep Learning — an onerous endeavor to recreate the complexities of a human brain with artificial neural networks — giving machines a mind of their own.
As technology perpetuates in its advancements, Deep Learning pundits are all leaning towards one goal, which is to create an Artificial General Intelligence — a machine capable of executing any forms of operations, akin to a human being.
The power of code
Every single quantum leap you read above was possible because of computer programming. To illustrate, the Curiosity Rover was pre-programmed beforehand so that it can explore Mars on its own without human intervention; producing the image of a black hole required an algorithm to collect image data from a network of satellites from the surface of Earth.
This medium of communication with computers is what engendered many scientific breakthroughs we see today. And without it, our society will stay stagnant.
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Everyone can code
In this epoch of growing exponential data, I believe everyone should procure the art of coding. Founders, CEOs, business leaders, VCs, even senior citizens, and youngsters. As the economic gap continues to widen and inequality perpetuates, the skill to code will be indispensable and essential for survival.
The good news is anyone can learn how to code! The bad? Coding is hard. But as long as you possess the attributes: curiosity, determination, and sheer will, you can do it. Writing code is also all about problem-solving. It’s the underlying notion behind programming. It’s often used to automate a monotonous task.
Moreover, one of the best ways to learn how to code is with practice, lots and lots of practice and make coding a habit . So, what better way to improve your skills when learning to code than through coding challenges and competitions?
Here are 20 websites I have collected which helps you practice programming and endows the opportunity to solve complex algorithmic problems.
The list is not ranked in any order. So scroll down now and enjoy it!
The template I use to review the websites
Introduction : Features: Best qualities:
The list of coding websites
HackerEarth is a popular coding platform that features over 8000 questions, 2000 challenges, and 1000 hackathons. It is also trusted by hiring managers across 1000+ companies. This platform has a thriving community of 3 million developers.
- Practice (basic programming questions)
- Contests (from beginners to week-long marathons)
- Hackathons (solving real-world problems and business challenges)
- Data Science competitions (testing your data science skills)
Best qualities : The website shows the days left in competitions and contests, and it has a developer assessment software that shows your progress. There is also a remote interview feature plus analytics for companies to see your statistics.
HackerEarth | Helping 3M+ developers level up and 1000+ recruiters hire top tech talent.
Helping 3m+ developers be better through coding contests, data science competitions, and hackathons. trusted by….
HackerRank is a hiring platform that is the de facto for evaluating developer skills for over 2,000 companies around the world. By enabling tech recruiters and hiring managers to objectively evaluate talent at every stage of the recruiting process, HackerRank helps companies hire skilled developers and innovate faster.
- Coding practices
- interview preparations
Best qualities: HackerRank is one of the top coding practice websites out there. It is well-known for matching developers with great companies and is useful for both the employer and the employee.
Join over 7 million developers. Practice coding, prepare for interviews and get hired.
Exercism is in one sentence — “Code practice and mentorship for everyone”. It has 3,173 exercises across 51 languages to level up your programming skills, and insightful discussion with their dedicated team of welcoming mentors. The best part, it’s 100% free forever.
- Language track
- Personal mentoring
- Practice mode
Best qualities: Exercism starts off with language tracks that allow users to choose their preferred languages. Moreover, there are human mentors who will check your code and help you improve as you progress. This makes the platform perfect for total beginners who want to deepen their understanding of a new programming language.
Level up your programming skills with 3,133 exercises across 52 languages, and insightful discussion with our dedicated…
SPOJ is a simple website with tons of coding challenges. These challenges help you become a true programming master and gives you the skill to build efficient algorithms.
- Discussion page
Best qualities: SPOJ has tons of mind-boggling coding challenges that will really test your skills. There are contests as well for you to participate in to showcase your skills.
Sphere Online Judge (SPOJ)
Spoj (sphere online judge) is an online judge system with over 315,000 registered users and over 20000 problems. the….
Programmr is an online interactive platform for anyone to learn and practice coding. They believe that the best way to learn is at your own pace in a self-taught environment. Programmr claims to make the world’s best coding simulators, where you can code and run all kinds of programs.
Best qualities: Programmr has an amazing online coding simulator and a B2B API that allows anyone to integrate coding widgets into websites.
Programming Challenges | Programmr
Sharpen your coding skills in the most entertaining way by solving programmr’s coding challenges don’t forget to….
6. TopCoder Challenges
TopCoder is a competitive programming platform. It provides a collection of algorithmic challenges that you can tackle in their own personal code editor. There’s always challenges up and running on the website and you can always participate if you’re up for it.
Best qualities: The challenges have specific deadlines as well as prizes shown clearly on each one of them. They also show what kind of languages or libraries are needed. Although these challenges are not for beginners, they are very well built.
Topcoder is a crowdsourcing marketplace that connects businesses with hard-to-find expertise. The Topcoder Community…
CodeForces is a collaborative platform where coders can participate in “rounds” where a time limit is set and points are distributed to the participants. CodeForces also has contests, problem sets as well as groups for coders to have at it.
- Problem sets
Best qualities: CodeForces is great for programmers who seek for fun challenges to build up their skills and join groups that suit their needs. The Gym feature is also very unique where coders can train their skills in specific challenges and see their standing at the end.
Hello, Codeforces community! I’m glad to invite you to Codeforces
Codewars is a well-designed platform where users work together to create challenges. There are two groups of people making it work, the creators who authorize kata to teach various techniques, solve kata with solutions that enlighten others, and comment with constructive feedback, and the leaders will moderate the content and community.
- Kata (coding practices)
- Kumite (1v1 challenges)
Best qualities: Codewar has a captivating interface with unique ways of presenting the challenges, naming them as Katas, where coders gain skills and challenge other coders in Kumite. It’s one of the best places to learn to code and to have fun at the same time.
Sign in | Codewars
Codewars is where developers achieve code mastery through challenge. train on kata in the dojo and reach your highest….
CodeChef is a competitive programming platform created as a platform to help programmers elevate their skills in the world of algorithms, programming, and contests. They promote the culture of learning and friendly programming, with a huge community of problem curators.
- Host contests
- Campus chapter
Best qualities: CodeChef has is one of the biggest competitive programming platforms. They open their platform for anyone to host programming contests and a feature called campus chapter as a tool for programming clubs to utilize. They also host 3 contests each month where prizes are given.
CodeChef | Programming Competition,Programming Contest,Online Computer Programming
Codechef — a platform for aspiring programmers codechef was created as a platform to help programmers make it big in….
CodeGym is an online Java Programming that is 80% based on practice. Anyone who wants to learn Java, here is the place to go.
Best qualities: CodeGym has practical tasks for beginners in Java to learn about all they need to know. They also have instant solution verification so that mistakes can be found immediately. CodeGym also utilizes the latest teaching techniques, with stunning visualizations and games.
CodeGym is an online course to learn Java programming
Codegym is an online java programming course that is 80% based on practice there are tons of good books on the…, 11. codepen challenges.
CodePen is a cool online IDE that allows you to write code in your browser and see the result just as you build it. CodePen challenges is a place for leveling up your skills by building things. Each week, new challenges appear for you to tackle, and the best “Pens” get picked.
Best qualities: CodePen challenges are super fun and its a place for creativity and collaboration. There’s no competition at all because there’s nothing to lose, but you do gain skills through these challenges.
CodinGame, our goal is to let programmers keep on improving their coding skills by solving the world’s most challenging problems, learn new concepts, and get inspired by the best developers.
Best qualities: CodinGame helps people learn coding in the form of games, allowing them to learn the fun way. Developers can also ask for help from mentors to review their codes and compare solutions with each other.
Coding Games and Programming Challenges to Code Better
Learn new concepts by solving fun challenges in 25+ languages addressing all the hot programming topics. in a matter of….
LeetCode is the best platform to help you enhance your skills, expand your knowledge and prepare for technical interviews. It’s used by hundreds of thousands of programmers for their amazing collection of algorithm practices from Amazon, Facebook, Google, LinkedIn, etc. There are over 1400 questions to practice.
Best qualities: LeetCode has an explore tool that helps programmers progress towards the next step in their programming career. LeetCode prepares them for technical interviews, and are involved in helping companies hire top talents as well.
Problems — LeetCode
Level up your coding skills and quickly land a job. this is the best place to expand your knowledge and get prepared….
GeeksForGeeks is the website for geeks. It has tons of resources on programming and algorithms. It also has an interview section to help programmers win their dream jobs. There’s also an excellent collection of C and C++ puzzles for programmers to solve.
Best qualities: GeeksforGeeks has myriads of articles teaching topics such as data structures, algorithms, Computer Science, and quizzes that test for knowledge and comprehension. It’s a great place to soak up some CS knowledge.
Puzzles — GeeksforGeeks
Recent puzzles puzzles c puzzles c++ puzzles puzzles: puzzle 1 | measure 45 minutes using two identical wires puzzle….
If you are studying algorithms and computer programming, chances are you’ve heard of Project Euler. A collection of mathematical problems made for problem solvers who are interested to combine mathematics and programming, Project Euler requires the use of mathematics to form algorithms and arrive at efficient solutions, and computer programming to actually solve it. These problems range in difficulty and they are not a walk in the park.
- Archived problems
Best qualities: Although the website does not have a built-in code editor or solution checker, this will be a good opportunity for programmers to download an IDE and code them on it. Moreover, solving these problems helps you develop skills that will be indispensable as a programmer, as mathematics is the underlying foundation of algorithms and data structures.
Archived Problems — Project Euler
The problems archives table shows problems 1 to 684. if you would like to tackle the 10 most recently published….
16. URI Online Judge
The URI Online Judge is developed by the Computer Science Department of URI University. The main goal of the project is to provide programming practice and knowledge sharing. Their website has a friendly UI and it contains more than 1000 problems divided in 8 big categories, solved with 11 languages.
- Problem repositories
- Competition and ranking
Best qualities: URI his developed by university students, which means they have the mindset of beginners who want to learn coding in a fun way. Moreover, the problems are well-structured and divided accordingly, starting with beginners' categories, and gradually into more complex topics such as computational geometry and graphs.
URI Online Judge
Uri online judge is a project developed for you our goal is to provide a platform where you can learn, practice and….
17. Reply Challenges
Reply Challenges is a series of challenges designed by “Replyers” and open to anyone who loves technology and online competitions. Reply Challenges are all about having fun and showcasing talent in areas like coding, cybersecurity, creativity, and investments. There are lucrative prizes for each challenge as well — Macbook Pro 16, Airpods Pro, etc. Challenges are open to students and professionals.
- Investment challenges
- Code challenge standard
- Code challenge teen
- Cybersecurity challenge (Coming soon)
- Creative (Coming Soon)
Best qualities: Reply Challenges are fun challenges with attractive prizes. They are very diverse and anyone is free to join.
A series of challenges designed by replyers and open to anyone who loves technology and online competitions. reply….
18. KickStart — Google’s Coding Competitions
Kick Start is a competition by Google which offers programmer around the world a chance to develop their skills through online competition round. Each round lasts for 3 hours and they feature algorithmic challenges developed by Google engineers so that you can get a taste of what it takes to work at Google. Their rounds are held periodically so that everyone gets a chance to participate.
Best qualities: The top-ranked programmers are given a chance to be interviewed and maybe even land a job at Google.
Hashcode is another great coding competition held by Google.
Kick Start — Google’s Coding Competitions
Hone your coding skills with algorithmic puzzles meant for students and those new to coding competitions. participate….
19. Code Jam
Code Jam is Google’s longest-running global coding competition, where programmers of all levels put their skills to the test. Participants must work through a series of algorithmic puzzles to win a spot in the World Finals, for a chance to be the champion and win a lofty prize of $15,000.
Best qualities: Code Jam challenges programmers around the world to solve difficult algorithmic problems in the form of 4 online rounds, and the annual Code Jam World Finals is held at different international Google offices every year. This grandiose challenge allows programmers of all levels to gain experience and motivate them to do improve their skills for a spot in the finals.
Code Jam - Google's Coding Competitions
Put your coding skills to the test as you work your way through multiple rounds of algorithmic coding puzzles for the…, 20. kaggle learn.
Kaggle is famous for being the place where data scientists collaborate and compete with each other. But they also have a platform called Kaggle Learn where micro-courses are provided. They are mini-courses where data scientists can learn practical data skills that they can apply immediately. They call it the fastest (and most fun) way to become a data scientist or improve your current skills. Courses available are — Python, Pandas, SQL, and, Data Visualization.
Best qualities: These micro-courses boil down complex topics down to key components which help beginners learn the important topics and gain the necessary skills in no time. Their built-in code editor, kernel, is easy to use and great for beginners.
Learn Python, Data Viz, Pandas & More | Tutorials | Kaggle
Practical data skills you can apply immediately: that's what you'll learn in these free micro-courses. they're the….
SoloLearn is one of the best places to learn how to code, with over 39 million learners, 1784 lessons, and 14k quizzes. I started learning how to code HTML and CSS on this website and it’s amazing.
- Great website with code playground and forums
- Mobile app to learn on the go
- Free certificates
Best Qualities: The best thing about SoloLearn is that all courses are free, on the website and mobile applications.
SoloLearn: Learn to Code
Join now to learn the basics or advance your existing skills.
Geektastic differentiates themselves from other platforms because they also offer Peer Reviewed Take Home challenges which are reviewed by experts from companies including Google and Amazon.
- When you join Geektastic as a Developer you complete their Express Challenges, which are short multiple choice challenges.
- The challenges are created by the community and use a ELO rating system (used for calculating the relative skill levels of players in zero-sum games such as chess) to grade both the challenges and the developers allowing you to compare yourself with the rest of their global community.
- If you get selected to join their Paid Review Team (kudos if you do!!) you can earn a nice side gig reviewing code challenges submissions from the community and their client base of high end tech businesses who use the platform to test the skills of job applicants for their software engineering and DevOps roles.
Technical Assessment & Code Challenge Platform
We analyse your candidate's code quality, problem solving skills, maintainability, test coverage and solution design….
23. Coding Bat
CodingBat is a free site of live coding problems to build coding skill in Java and Python ( example problem ). CodingBat is a project by Nick Parlante , a computer science lecturer at Stanford.
- The CodingBat problems are designed to have low overhead:
- short problem statements (like an exam)
- nothing to install
- immediate feedback in the browser
Best Qualities: The best thing about CodingBat is it’s simplicity and how it’s really all about building and practicing little code problems to solidify your code skills.
CodeSignal has a technical interview practice that helps you get ready for technical interviews by completing real-world assessments in an advanced IDE. It starts with customizing a personal study plan, then helps you master key topics by solving real-world questions.
- practice and understand how to apply core concepts asked in technical interviews
- Understand your strengths and weaknesses to know where you should be spending most of your time leading up to the interview
- Refresh your interview knowledge and verify your understanding of important skills and concepts frequently seen in technical interviews
Best Qualities: The best thing about CodingBat is it’s reliability and it’s used by many tech companies around the world.
Interview Practice | CodeSignal
Practice for technical interviews - complete assessments simulated with real-world questions in an advanced coding….
- limitless supply of bite-sized challenges, so you can rapidly advance your abilities.
- start on easy and progress at your own pace until you’re able to master the toughest challenges.
- simple game mechanics to make the learning process fun and addictive. Gain XP, unlock achievements and level up.
Best Qualities: The best thing about Edabit is it’s easy to use and clean interface and the shuffle feature that adds the fun to coding tutorials.
Edabit // Learn to Code with 10,000+ Interactive Challenges
Learn to code with fun, bite-sized challenges. gain xp, unlock achievements and level up. it's like duolingo for…, call for action.
In this era, programming is a skill as important as making fire and hunting for food back in the primitive ages.
That’s not to say a person without this skill will be doomed, it just means people who have this skill will dominate and succeed. It’s like drinking a special potion that gives you magical power or being hit by lightning and given super speed.
Coding should be treated like a superpower, with the impact it has brought to our world, and the technology it has made possible.
- If you’re a complete beginner, choose a programming language first.
- Take part in challenges such as #100DaysofCode, which can provide you the motivation to start coding as a complete beginner, and to keep on coding. Or you can get a friend to code with you.
- Choose one or two from the above list, find the one that suits you and stick to it till the end.
- Don’t look at the answers right when you get stuck, you won’t learn anything. Instead, make sure you get the basics right and then only attempt the challenge again.
- Join communities on Reddit, Discord, etc, to ask questions.
- Install an IDE to work on some of the problems, or use a Jupyter notebook.
It’s never too late to start coding today. If you are already a programmer, or an expert in the field, kudos to you, and I hope that you’ll flourish in your journey!
I hope you found the list useful and that I have motivated you to start coding.
Thanks for reading and Stay Safe!
Here are a few other articles for you I wrote about Learning Data Science
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The 10 Most Popular Coding Challenge Websites [Updated for 2021]
A great way to improve your skills when learning to code is by solving coding challenges. Solving different types of challenges and puzzles can help you become a better problem solver, learn the intricacies of a programming language, prepare for job interviews, learn new algorithms, and more.
Below is a list of some popular coding challenge websites with a short description of what each one offers.
TopCoder is one of the original platforms for competitive programming online. It provides a list of algorithmic challenges from the past that you can complete on your own directly online using their code editor. Their popular Single Round Matches are offered a few times per month at a specific time where you compete against others to solve challenges the fastest with the best score.
The top ranked users on TopCoder are very good competitive programmers and regularly compete in programming competitions. The top ranked user maintains his own blog titled Algorithms weekly by Petr Mitrichev where he writes about coding competitions, algorithms, math, and more.
Coderbyte provides 200+ coding challenges you can solve directly online in one of 10 programming languages (check out this example ). The challenges range from easy (finding the largest word in a string) to hard (print the maximum cardinality matching of a graph).
They also provide a collection of algorithm tutorials , introductory videos, and interview preparation courses . Unlike HackerRank and other similar websites, you are able to view the solutions other users provide for any challenge aside from the official solutions posted by Coderbyte.
3. Project Euler
Project Euler provides a large collection of challenges in the domain of computer science and mathematics. The challenges typically involve writing a small program to figure out the solution to a clever mathematical formula or equation, such as finding the sum of digits of all numbers preceding each number in a series.
You cannot directly code on the website in an editor, so you would need to write a solution on your own computer and then provide the solution on their website.
HackerRank provides challenges for several different domains such as Algorithms, Mathematics, SQL, Functional Programming, AI, and more. You can solve all the challenge directly online (check out this example ).
They provide a discussion and leaderboard for every challenge, and most challenges come with an editorial that explains more about the challenge and how to approach it to come up with a solution.
Currently, if you don't solve the problem, then you can't see the solution of others. If you also try to check the editorial before solving the problem, then you won't get the point for solving the problem at all.
As an example, here I haven't solved the problem, and I am trying to check others' submissions:
And here, I haven't solved the problem, and I am trying to check the editorial:
HackerRank also provides the ability for users to submit applications and apply to jobs by solving company-sponsored coding challenges.
CodeChef is an Indian-based competitive programming website that provides hundreds of challenges. You are able to write code in their online editor and view a collections of challenges that are separated into different categories depending on your skill level (check out this example ). They have a large community of coders that contribute to the forums, write tutorials , and take part in CodeChef’s coding competitions .
Exercism is a coding challenge website that offers 3100+ challenges spanning 52 different programming languages. After picking a language that you'd like to master, you tackle the coding challenges right on your machine (Exercism has their own command line interface that you can download from GitHub).
It is a bit different from other challenge websites, however, because you work with a mentor after completing each challenge. The mentor reviews your answers online and helps you improve them if needed. Once your answers have been approved and submitted, you unlock more challenges.
Codewars provides a large collection of coding challenges submitted and edited by their own community. You can solve the challenges directly online in their editor in one of several languages. You can view a discussion for each challenges as well as user solutions.
LeetCode is a popular Online Judge that provides a list of 190+ challenges that can help you prepare for technical job interviews. You can solve the challenges directly online in one of 9 programming languages. You are not able to view other users' solutions, but you are provided statistics for your own solutions such as how fast your code ran when compared to other users' code.
They also have a Mock Interview section that is specifically for job interview preparation, they host their own coding contests , and they have a section for articles to help you better understand certain problems.
Sphere Online Judge (SPOJ) is an online judge that provides over 20k coding challenges. You are able to submit your code in an online editor . SPOJ also hosts their own contests and has an area for users to discuss coding challenges. They do not currently provide any official solutions or editorials like some other websites do, though.
CodinGame is a bit different from the other websites, because instead of simply solving coding challenges in an editor, you actually take part in writing the code for games that you play directly online. You can see a list of games currently offered here and an example of one here . The game comes with a problem description, test cases, and an editor where you can write your code in one of 20+ programming languages.
Although this website is different than typical competitive programming websites such as the ones mentioned above, it is still popular amongst programmers who enjoy solving challenges and taking part in contests.
This list was based on a few things: my own experiences using the websites, some Google searches , Quora posts , and articles such as this one and this one . I also frequented some forums and subreddits such as r/learnprogramming to see what websites were usually recommended by the users there. Disclaimer: I work at Coderbyte which is one of the websites mentioned above.
CEO & Founder at Coderbyte.
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7 Best Coding Challenge Websites in 2020
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Every coder wants to be one of the best! Yes, it’s true. But do you ever think how can someone be considered as the best coder? Okay, suppose there is a guy who wants to be the best racer, so can he do that by just practicing it? Not, what he has to do is to prove himself, get the better of others, and conquer the battle. Similarly, if you want to be the finest coder, you have to face challenges and showcase your programming skills . And, the best way to do the same is Competitive Programming and Coding Competitions .
The Coding Contests or Competitions provide you the opportunity to analyze your skills and proficiency, and to compare yourself to other programmers across the world. Apart from these, various scholarships , prizes , jobs & internships opportunities are also provided to the participating programmers. There are various platforms (or websites) that conduct these coding challenges online on a regular basis. Best 7 Coding Challenges Websites are listed below along with a brief description.
TopCoder is one of the most popular platforms for online programming competitions. Anyone can join the Topcoder Community to participate and compete in challenges. The TopCoder Community has majorly 4 segments – Design , Development , Data Science , and Competitive Programming . The design community deals with Information Architecture and UI/UX/CX Design whereas the Development segment looks into Bug Bash, Code, First-to-Finish (F2F), Quality Assurance and UI Prototype Challenges. There are various data science challenges also named as Marathon Match (MM) , Data Science First to Finish , Data Science Sprint & Ideation and Data Visualization . The Competitive Programming domain of Topcoder community revolves around Single Round Matches (SRMs) offered on weekly basis at a specific time in which all participants compete against each other to solve the problems as fast as possible. Some of the major stats of the TopCoder Community are listed below:
- There are 5 times more engineers than Microsoft, Facebook, and Twitter combined!
- Around 1,400+ Crowdsourcing challenges are completed per quarter.
- The Community has around 1.5M members in over 190 countries.
- Also, nearby 1,800 new members join per week.
HackerRank is a leading platform for competitive programming challenges where you have to solve the problems as per the given specifications. HackerRank offers you to solve these programming challenges in any of various programming languages such as C , Java , Python , Ruby , etc. Apart from this, participants can solve the problems in various computer science domains like algorithms, machine learning, and artificial intelligence. You can also earn badges by solving challenges on the HackerRank website and these badges will be added to your profile. The type of contests hosted by HackerRank are listed below:
- 101-Hack – A monthly algorithmic contest in which five challenges have to be solved within 2 hours.
- HourRank – The shortest contest format in which 3-4 algorithm challenges need to be solved within 1 hour.
- Week of Code – A weeklong algorithm contest where one new challenge is offered each day. Also, the challenges become more complicated as the day passes.
- Ad Infinitum – A 48-hour contest of Mathematics conducted every three months.
- Real Data/Machine Learning Contests – A weeklong contest focuses on real-world data skills and requires the use of machine learning techniques.
- Language/Domain Specific Contests – These are the contest based on various programming languages like C, Java, Python, etc.
- Company Contests – The contests sponsored by specific companies that are looking to hire developers. The nature of this contest varies as per the requirements of the sponsoring companies.
- World CodeSprint – It is a 24-hour contest having 7-8 challenges to be solved.
3. International Collegiate Programming Contest (ICPC)
The International Collegiate Programming Contest (ICPC) is one of the most renowned competitive programming competition. However, from 1977 to 2017 , ICPC was held under the authority of ACM and was termed as ACM-ICPC . ICPC contests are team competitions and as per the rules, each team must consist of 3 students representing their university. The ICPC features various levels of competition – Local Contests , Regional Contests , Regional Championships , and The World Finals . Every year, the ICPC regionals start from the local competitions among classmates to find out who may represent their university and the final regional contest determines the teams moving forward to the World Finals. The teams leading at each regional level contest from 6 different continents qualify to compete at the World Finals. During each contest, the teams of 3 are given 5 hours to solve around 10+ programming problems . The solutions must be submitted in C , C++ , Java , Python or Kotlin language. Some of the major stats of the International Collegiate Programming Contest (ICPC) are listed below:
- It is one of the oldest programming competition in the world.
- More than 50,000 students are part of the ICPC family.
- Around 3,000 universities in 111 countries are associated with the ICPC.
- ICPC has around 400 on-site competitions.
CodeChef is a competitive programming website that offers several challenges for aspiring programmers to practice and sharpen their programming skills through various online contests. CodeChef conducts a programming competition at the start of every month and also conducts 2 smaller programming contests at the middle and end of the month. You can submit your solution in any of the programming languages as the contests accept solutions in over 55+ programming languages including C, C++ , Java, and Python. Apart from these contests, CodeChef also offers various algorithm tutorials and forum discussions to make the journey of computer programming more feasible. You can receive points and move up through the CodeChef ranks which is really worthy. There are various coding competitions where you can show your programming skills such as – Monthly Programming Contests, Cook-off and Lunchtime Coding Contests. Some of the major stats regarding CodeChef contests are listed below:
- CodeChef has around 1,250,000+ programmers from 12,000 institutions.
- There are approximately 3200+ programming contests with around 92 million+ submissions.
- The contests have the prizes of around INR 20,000 for Indian Community and $700 for Global Community.
5. Geeks Coding Challenge (GCC)
Geeks Coding Challenge (GCC) is a 3-day coding contest organized by GeeksforGeeks (one of the leading website in the Computer Science domain!). The contest is conducted online where you can solve various coding problems and can compete with other programmers online. You can solve the problems from any of the following programming languages – C++ , Java or Python . Also, the total prize amount for Geeks Coding Challenge is worth more than 6 Lakh Rupees consisting of cash prizes, accessories, courses, etc. One thing to remember here is that the number of seats for the Geeks Coding Challenge (GCC) is limited, so you have to make sure to register yourself before the seats get filled and the registration will be closed. Also, there is not any participating fee for this contest. The contest is divided into 3 rounds which are described below:
- Round 1 – It is the very first round where all the registered candidates have to appear for a 90 minutes coding challenge. The top 250 candidate s from this round qualify for the next round of the contest.
- Round 2 – The second round is a 120 minutes coding challenge where the top 250 qualified candidates from the first round compete with each other. The top 100 candidates from the second round qualify for the final round.
- Round 3 – It is the final round where all the top 100 performers from Round 2 compete for a 120 minutes challenge.
LeetCode is the leading platform that offers various coding challenges to enhance your coding skills. It offers various weekly and biweekly programming competitions for the participants. The contests are generally of a duration of 90 minutes. You can solve the challenges in their own online editor (named as Playground) in any one of the supported programming languages. Apart from the Coding Contest, various additional features such as job interview preparation, discussions, etc are also provided on LeetCode. Some of the major stats of the LeetCode are listed below:
- LeetCode is one of the largest tech communities with millions of active users.
- You can practice over 1400+ coding problems and the number is increasing day by day!
- LeetCode supports over 14 popular coding languages that make it more preferable.
Also, at the end of each contest, you will be rewarded with rankings and points which can help you in getting a job in top tech giants.
Codeforces is a Russian website that hosts competitive programming competitions where the number of competitive coders across the world competes with each other. The contests conducted by Codeforces allow you to write solutions to the problems that are tested during the contest. Those who pass that set of solution tests receive the opportunity to go through the sources of other contestants, search for mistakes there and suggest the tests on which these solutions do not work. Accordingly, you can hack or challenge others’ solutions and can earn points through it. Then after the contest, all the solutions that pass the pretests and have not been hacked or challenged are tested on the final set of tests. The best thing about Codeforces is that the contests are regularly conducted here as every month they organize nearly 6 contests. Also, participation in the contests is free and open to everybody. Codeforces offers various type of coding challenges and features such as –
- Short format Contests with a duration of 2 hours .
- Educational Contests of 2-2.5 hours duration conducted 2-3 times in a month.
- You can challenge or hack other contestants’ solutions as well.
- You can also solve problems from previous contests for learning objectives.
Programming needs a lot of patience. Start participating in different competitive programming contests and improve yourself day by day. Show your ranking in your resume and this will also help you in landing a job in top tech companies.
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11 Websites To Practice You Coding And Your Problem Solving Skills
11 websites to practice your coding and problem-solving skills.
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10 websites to practice coding problems: Our picks
Whether you're just starting out as a coder or want to advance your coding skills, tackling programming problems is part of the plan.
Convenient, free, and even fun, coding problem websites challenge your abilities with individual exercises, friendly challenges, and insightful assessments.
Practicing your coding through these websites may increase your knowledge, build your skills, and prepare you for programming job interviews.
Top websites for practicing your coding skills
Should a humanities major learn to code?
Can a humanities student learn coding? Absolutely. Coding is not strictly for STEM students — it can benefit you no matter your degree.
How hard is it to learn coding ? Starting from scratch can be difficult, but coding challenges designed to test and advance your skills may help. We rounded up 10 great websites for coding problems and listed them alphabetically for you.
Each website offers a collection of resources for learning coding or advancing what you already know.
CodeChef lets you choose among thousands of problems to practice skills like sorting, data structures, and dynamic programming. Problems are sortable by difficulty. Code Chef's practice problems allow you to answer in one of over 50 programming languages as you prepare for its internal or external monthly contests.
CodeChef offers self-guided learning opportunities and mentoring programs alongside a community of coders, coding bootcamps, and tech certification programs.
Designed for coding practice and improvement, Coderbyte offers code challenges and courses aimed at helping you prepare for job interviews.
You can sign up for a free challenge and free trial. A monthly subscription to Coderbyte costs $35 and an annual subscription is $150. Both give you access to all of Coderbyte's resources.
Launched in 2012, Codewars provides practice kata, or small coding exercises, that you advance through as you build your skills. Codewars' kata are available in nearly 60 programming languages and in levels from beginner to advanced.
You can develop your own kata, engage with the Codewars community, and master one or multiple languages in the process. Feedback and creative learning facilitate creative thinking and innovation among Codewars' users. Codewars offers resources for educators and companies as well.
With more than 25 supported languages, CodinGame provides challenge-based programming training through games, puzzles, and competitions.
CodinGame's resources let you build your programming abilities, learn new concepts, and interact with fellow coders through easy, medium, hard, and very hard exercises.
CodeinGame's leaderboard and prizes earn you recognition from your peers and track your progress. Free live streams, blogs, and discussion forums for developers accompany sourcing, screening, and retention programs for recruiters.
With human-reviewed technical assessments, Geektastic lets companies customize coding challenges for talent acquisition and engineering team training. If you have coding experience, you can join Geektastic's reviewer community to create and test those challenges — and get paid to review candidates' performance.
HackerRank serves as a technical interview platform, but also provides coding practice to over 18 million users. Challenges offered by HackerRank cover topics including algorithms, Java, Python, Ruby, and data structures.
HackerRank's challenges allow you to test your code, debug it, and win one of its sprint, company, language, or timed challenges. You can also earn certifications in specific skills or complete interview preparation kits. Pricing ranges from $25/month for interview content to $819/month team subscriptions.
LeetCode provides more than 2,250 practice problems to its programmer community. Individual challenges in topics like algorithms, database structures, and dynamic programming accompany entire study plans.
LeetCode's programming skills study plan integrates three modules offered at easy, medium, or hard difficulty levels. LeetCode supports 14 programming languages and houses a playground tool to help you test, debug, and write code.
Sign-up is free. LeetCode Premium offers access to additional tools and premium content for a monthly subscription of $35 or an annual fee of $159.
8. Project Euler
Named for mathematician Leonhard Euler, Project Euler began in 2001. Recent and archival content is available for registered users at no cost.
Project Euler offers computational programming problems combining mathematics with computer and programming skills. With 108 programming languages and more than one million users, Project Euler provides problems with varying difficulty.
Sphere Online Judge, or SPOJ , trains users to code and build efficient algorithms through more than 20,000 practice problems. Scoring categories for problems include challenges, tutorials, and riddles. Rankings and a status board accompany running contests that support more than 45 programming languages and compilers.
SPOJ offers a flexible testing system to automatically assess user-submitted programs. Users can design their own contests or take part in an online course at all programming levels, but it is ideal for students.
TopCoder's community of designers, developers, data scientists, and competitive programmers build their skills, show their expertise, and earn money as they improve their coding abilities. TopCoder pays individuals for their work, sells it to corporate clients, and hosts competitions designed to highlight top coding talent worldwide.
Customers use TopCoder to hire freelancers on-demand, set challenges for the coding community, and find teams for projects.
This article was reviewed by Monali Mirel Chuatico
In 2019, Monali Mirel Chuatico graduated with her bachelor's in computer science, which gave her the foundation that she needed to excel in roles such as data engineer, front-end developer, UX designer, and computer science instructor.
Monali is currently a data engineer at Mission Lane. As a data analytics captain at a nonprofit called COOP Careers , Monali helps new grads and young professionals overcome underemployment by teaching them data analytics tools and mentoring them on their professional development journey.
Monali is passionate about implementing creative solutions, building community, advocating for mental health, empowering women, and educating youth. Monali's goal is to gain more experience in her field, expand her skill set, and do meaningful work that will positively impact the world.
Monali Mirel Chuatico is a paid member of the Red Ventures Education Integrity Network.
Last reviewed April 21, 2022.
The best coding challenges and competitions platforms on the internet for developers to learn the skills ... Writing code is also all about problem-solving.
Most importantly, solving problems in an. ... Kaggle is an online community platform for data scientists and machine learning enthusiasts.
Solving different types of challenges and puzzles can help you ... is one of the original platforms for competitive programming online.
General Innovation Challenges: · 1. Open Innovation Platform · 2. Agorize · 3. Herox · 4. freelancer · 5. Grabcad · 6. Open Ecosystem Network.
HackerRank is a leading platform for competitive programming challenges where you have to solve the problems as per the given specifications
Harness the power of our global community of 500,000 problem solvers, our global reach to millions more, all combined with our Challenge Driven Innovation™
11 websites to practice your coding and problem-solving skills · coderbyte · topcoder · codewars · Leetcode · hackerrank · exercism · codechef
Solve each problem using programming languages. ... Google Coding Jam is a one-of-a-kind platform where programmers are pitted against each
Sphere Online Judge, or SPOJ, trains users to code and build efficient algorithms through more than 20,000 practice problems.
CodinGame is a challenge-based training platform for programmers where you ... Learn new concepts by solving fun challenges in 25+ languages addressing all