Monday to Sunday every day 1 challenge will go live. (Easy to Hard) To get the full score for a challenge, you need to solve it within 24 hours of the time when it goes live. At the end of every 24 hours score for each published challenge decreases by 10%. When you submit your solution, it runs on basic tests, and every 24 hours your solutions run on extended tests. If you are not happy with your score you can resubmit the next day (but remember 10% penalty!)
Unlike in Codeforces, you can get a partial score for a problem according to the set of passed tests, so if you do not know the complete solution, it makes sense to submit partial one.
Score for each challenge is the best score of all your submissions of that challenge. Score for the contest is the sum of scores of problems. Contestants are ranked by the score sum, ties are broken by the time of the last submission that increased the score of a participant.
The contest was prepared by me mfv (HackerRank: mfv), zemen (HackerRank: zemen) and tested by niyaznigmatul (HackerRank: niyaznigmatullin). Special thanks to the contest administrator shashank21j and editor AllisonP.
The contest is rated and top 10 get T-shirts.
Residents of the following countries and territories are not eligible to win prizes including T-shirts due to legal restrictions in the USA. Learn more here: Antarctica, Afghanistan, Belarus, Bosnia and Herzegovina, Bouvet Island, Burundi, Cameroon, Central African Republic, Congo, Christmas Island, Crimea, Cuba, North Korea, Equatorial Guinea, Iran, Iraq, Laos, Lebanon, Libya, Moldova, Nigeria, Pakistan, Papua New Guinea, Russia, Serbia and Montenegro, Sevastopol, Somalia, Sudan, Syria, Ukraine, Venezuela, Yemen, Zimbabwe.
Residents of the following countries and territories are not eligible to win T-Shirts due to heavy international tax charges required for both the recipient and HackerRank: Bangladesh, Dalaras, Kazakhstan, Philippines, Sweden and Ukraine.
Good Luck and Have Fun!
P.S. If your solution passes preliminary tests please test it yourself thoroughly. For example, check that its output matches one of a naive solution on small inputs and check that it works within the time limit on the max test.
UPD: Congratulations to the winners!