Challenges
Dive into our coding challenges to have fun and acquire new skills. Join us in chat to discuss!
Challenge #15: Mystery Alphabet Decoder
We are experimenting with more community authored Challenges, if you are interested in writing your own challenge, please head to the sandbox and post your idea there. This challenge was written by M--...
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Challenge #14: Signal from Noise [COMPLETED]
Update on January 8, 2025: Huge thanks to everyone who participated in the challenge. The conditions for signal/noise were tricky, and we appreciate the careful implementations! The correct sum of the ...
Challenge #13: Integer sorting in a grid [COMPLETED]
Update on October Dec 4: Huge thanks to everyone who participated in the challenge. The correct answer is that 45 of the sets were impossible to put into the grid. We received 70 responses from 68 ...
- 2,249
Challenge #12: Spooky Halloween scene [COMPLETED]
Update, Nov 13: Thanks to all that participated and voted in this challenge! In terms of votes, top 3 entries were: 1st place: Phil with a spooky house scene 2nd place: Death-is-the-real-truth (...
Challenge #11: Taco crawl optimization [COMPLETED]
Update on October 23: Huge thanks to everyone who participated in the challenge. The correct routing was [0,7,5,6,2,10,4] for 97 tastiness and 2.8945 tastiness/distance. 43 of the 53 entries provided ...
Challenge #10: Road safety challenge (joint with Kaggle) [COMPLETED]
Update, Nov 1, 2025: The challenge is now complete. Thanks to those that participated. We'll review the entries and soon announce the users that receive the badge. Kaggle is a platform for Machine ...
Challenge #9: Random Number Generator [COMPLETED]
Update: October 6, 2025: Thanks to everyone who participated in this challenge! It was very interesting to see the diverse approaches to random number generation. Congratulations to the following ...
Challenge #8: Word ladder [COMPLETED]
Update, October 2, 2025: Appreciation to everyone who participated in this challenge! The correct length of the word ladders is as follows: [stone, money] [11] [bread, crumb] [11] [smile, giant] [11] ...
- 245k
Challenge #7: Pangram checker [COMPLETED]
Update, October 2, 2025: A HUGE thanks to everyone who participated in this challenge! The correct answer is: 819 Non-Pangrams, 132 Pangrams (non-perfect) and 49 Perfect-Pangrams. We are very ...
- 34.1k
Challenge #6: Integer Counting [COMPLETED]
Update on October 8, 2025: Thanks to everyone who voted on the entries! We received 281 votes from 59 users. There were a lot of great responses to this challenge. We appreciate the participation. We'...
Challenge #5: Traffic Light Simulator [COMPLETED]
Congratulations to Kamran for the best response to this challenge! We were impressed by your simulation and also the inclusion of variable weather elements. This Challenge is now closed but entries ...
- 34.1k
Challenges Sandbox – Help us create new challenges
We are making some upgrades to Challenges – one of which is allowing users to contribute their own! If you have an idea for a challenge, please post it as an entry here in this Sandbox, where it can ...
Challenge #4: Create a futuristic technology [COMPLETED]
Awards for the fourth Stack Overflow code challenge: Most Upvotes: Davide Fiocco Vision Architect: 12Kittens New Contributor: Prakhar Agarwal All of the awards given (aside from most upvotes) are ...
Challenge #3: Creating ASCII art snowflakes [COMPLETED]
Awards for the third Stack Overflow code challenge: Most Upvotes: André Serene Scene Creator: Ale_Bianco New Contributor: Michael Brown Most Customizable: FoxWise Snowflake Artisan: Newpzo All of the ...
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Challenge #2: Secret messages in game boards [COMPLETED]
Awards for the second Stack Overflow code challenge: Most upvotes: Ale_Bianco Puzzle prodigy: Anon Coward New contributor: Ayan Nayak Most imaginative: Bladeski Straight to the point: NullDev All of ...
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