January 2016 Contest -- Final Results

This was our second contest of the 2015-2016 season. A total of 2823 users logged into the contest during its 4-day span. Of those, 1997 participants submitted at least one solution, hailing from 72 different countries:

 1070 USA  146 CHN   64 VNM   63 ROU   59 IRN   50 CAN   41 RUS
   33 BLR   28 BGD   25 IND   24 DEU   24 BGR   21 KOR   20 MEX
   20 AUS   15 TUR   15 GEO   15 FRA   14 POL   14 HRV   12 GRC
   12 EST   11 UKR   10 KAZ   10 ITA   10 IDN   10 COL    9 THA
    9 BRA    8 SRB    8 JPN    8 ISR    7 MYS    7 HUN    7 CUB
    7 ARM    6 ZAF    6 TWN    6 TKM    6 FIN    4 VEN    4 SGP
    4 MDA    4 HKG    4 AZE    4 ARG    3 TUN    3 SYR    3 SVN
    3 EGY    3 AUT    2 SWE    2 SVK    2 NLD    2 MKD    2 LVA
    2 LTU    2 GBR    2 DOM    1 ZWE    1 BEL    1 NZL    1 NPL
    1 MAR    1 LBN    1 KGZ    1 ISL    1 GER    1 CZE    1 CYP

The average participant submitted solutions for 2.1 problems. In total, there were 4138 graded submissions, broken down by language as follows:

 1442 Java
 1157 C++11
 1130 C++
  148 Python 3.4.0
  117 Pascal
   88 Python 2.7.6
   44 C

Below are the detailed results for each of the platinum, gold, silver, and bronze contests. You will also find solutions and test data for each problem, and by clicking on any problem you can practice re-submitting solutions in "analysis mode". If you are logged in, you will also see your own specific results below alongside the contest(s) you took.

USACO 2016 January Contest, Platinum

The Platinum division had 424 total participants, of whom 303 were pre-college students. By design, the platinum contest this time was quite challenging, with only two perfect scores: Demi Guo from the USA in the pre-college group, and Ishraq Huda from Australia in the observer group -- congrats to both of you for this outstanding set of results! Full results are here.

USACO 2016 January Contest, Gold

The Gold division had 536 total participants, of whom 394 were pre-college students. The gold contest was also quite challenging, with a limited number of high scores.

All competitors who scored 600 or higher on this contest are automatically promoted to the platinum division -- congratulations to you all! Detailed results for those promoted are here.

USACO 2016 January Contest, Silver

The Silver division had 1037 total participants, of whom 880 were pre-college students. Many students performed quite well in this division.

All competitors who scored 700 or higher on this contest are automatically promoted to the gold division. Detailed results for those promoted are here.

USACO 2016 January Contest, Bronze

The Bronze division had 1165 total participants, of whom 921 were pre-college students. We saw a large number of very high scores in the bronze contest this time around as well.

All competitors who scored 750 or higher on this contest are automatically promoted to the silver division -- to all who were promoted, congratulations! Detailed results for those promoted are here.

Final Remarks

Another successful contest! This one was designed in particular to challenge our high-end competitors, and it seems to have certainly accomplished this goal, yielding a much smaller number of perfect scores in gold and platinum. The contest itself ran relatively smoothly, except for two issues: a load spike on Sunday evening caused sluggish website performance for about an hour, and we had a few test data bugs that needed correcting --- the data for the gold "lights out" problem was discovered to be buggy after the contest, so we replaced it and re-graded all of those submissions. We also replaced two test cases for the platinum "fort moo" problem, since they involved degenerate situations tha the problem statement did not address. Our apologies to those affected by these glitches -- we were a bit more lenient than usual with our gold-to-platinum promotion cutoff to compensate.

For those still waiting to achieve promotion, remember that USACO contests are designed to challenge even the very best students, and it can take a good deal of hard work to excel at them. Remember that the more practice you get, the better your algorithmic coding skills will become! To help you fix any bugs in your code, you are encouraged to consult the official solutions above and to make use of "analysis mode" to re-submit improved versions of your solutions.

A large number of people contribute towards the quality and success of USACO contests. Those who helped with this contest include Mark Gordon, Richard Peng, Nathan Pinsker, Chad Waters, Nick Wu, and Pasin Manurangsi. Thanks also to Amy Quispe for helping to maintain our social media presence (Facebook: https://www.facebook.com/UsacoContests, Twitter: (https://twitter.com/UsacoContests), our translators for allowing us to offer this contest in five additional languages, to Clemson CCIT for providing our main contest server, and to our sponsors for their generous support: Usenix, Dropbox, and D.E. Shaw.

Happy coding!

- Brian Dean ([email protected])
Director, USA Computing Olympiad
Associate Professor of Computer Science, Clemson University

Your Account