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Microsoft and Pragyan, NIT Trichy Hackathon partners with Spoj!

Microsoft and Pragyan, NIT Trichy presents Hackathon 2015 to be held at IFIM B School, Bangalore on 12th and 13th of December. It is a two day Hackathon where participants will have to develop a web/mobile app pertaining to the theme of the Hacakthon. There is no constraints on the platform or language. Participants can form teams at the venue (team of 3).

Prizes worth INR 1,00,000 and internships are at stake. All participants will receive a free merchandise. Food for the two days is provided and participants can stay at the venue overnight.

Register here: Open for first 200 registrations only. Registration deadline: 25th Nov 2015. Date of event: 12th to 13th December, 2015. The theme of the Hackathon will be disclosed two weeks prior to the event. Follow the page for more updates. is happy to be a part of this event!

NASA and Freelancer’s Space Contest

Join the NASA Tournament Lab (NTL) and as they host a series of contests to crowdsource some of the most complex problems being faced by astronauts on the cutting edge of space exploration. Your contribution to these contests will be used in software simulations and by astronauts aboard the International Space Station!

For the first several contests, help build tools for the Robonaut R2, a robotic assistant used to help humans work and explore in space. Why not take this chance to be a part of humanity's journey to go beyond Earth's orbit and explore the vast wonder of space? Join the contests now.

Enter Coding Chill-out zone

International programming contest in the Mediterranean region.

Remote session : 26.06 - 03.07 2015
On-line session is OPEN for any registered users. Two categories: students & IT Pros. Join today and share our passion for coding. Code from your own #CodingChillout zone and rank high! Grab paid GitHub plans and Cloud computing tokens offered by Octawave.

Are you in Malta?
GOTO: On-site event in Malta on 11th July @Microsoft Innovation Center. All in relaxed and chilling climate of Maltese islands ... Just simply Enter Coding Chill-out zone, add song to the event playlist...and do what you LOVE. Register today:

CodeChef SnackDown 2015 - Code Your Heart Out

CodeChef SnackDown is a multi-round programming contest open to all. The multiple online rounds will culminate at an onsite grand finale, where 25 teams from across the India will be flown down to the CodeChef headquarters in Mumbai, India. For the participants residing outside India, there will be a parallel online round for the finale. While the Indian teams will compete for the cash rewards worth INR 6 Lakhs and a job opportunity with Directi, the global participants will have a chance to win exciting prizes like MacBook Pro, Drone Quadcopters, and Go Pro Cameras. So, register your teams now and strengthen your chances of winning.


We present the long-awaited new, fresh, and crispy design of SPOJ! It's taken us a while to get here since 2004, but hey, it looks good - doesn't it? There's now a new feature for tagging and grading problems. We are also working to make SPOJ as mobile-friendly as possible. Stay tuned, because there are many more surprises to come!

Goodbye Pyramid

During the last six months, we have been gradually migrating our "checkers" (servers which execute submissions) from old to new machines. The procedure required some care since the new machines have significantly greater processing power. The main difficulty was adjusting the time limits for problems: in general, the new machines seemed to be more "tolerant" of slow solutions than the old ones. Over the 10 years of existence of SPOJ, our great community has produced over 13.5 million submissions (10 million of which on the old checkers) and we didn't want to rejudge all of them. So, we designed an algorithm for recalculating submission running times by interpolation. Data for reliable interpolation came from a real rejudge of a representative sample of 5% of the submissions, i.e., 511,000 submissions have been rejudged over the past six months. At the end, we changed the time limits of test cases keeping them in relation to running times of solutions.

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Lambda Days 2015 Challange

For the second year in a row Lambda Days come to Kraków to bring together people passionate about functional programming. The tickets are out and the only way to attend at the moment is to get high score in their special programming contest. If you are interested in participation visit

Banning cheaters

We have intensified banning cheaters (users who copy codes from the internet and submit them here). Soon all of them from "Cheaters" thread on forum will be banned. If you are a cheater you can avoid ban by disqualifying all your cheating submissions until we get to you. After mentioned thread all users from top100 (and then top256) will be x-rayed.


Please check out a new contest CONSTANT. It's dedicated to problems in which you have to evaluate as many digits as possible of famous constants like π, e or φ.

Even if you are not interested, you may find there a link to the world records in this field. You may be surprised.