The authors are from Romania.

The Eastern European countries, e.g. Romania, Russia, Poland etc are very strong in maths, computing/programming and science.

The Google Coding Contest and topcoder contests held in USA - the Eastern Europeans beats the Americans and Western Europeans.

From the Asian side, the coders from China are the most outstanding - Google Coding Contest, topcoder contests, ACM International and other computing contests.

* topcoder.com is a USA based company.

References:
A Growing Cadre Of Code Warriors: China's young programming hotshots are gaining global attention.
http://www.topcoder.com/tc?module=St...sroom&d2=index
2007 ACM Contest Winners Announced:
Warsaw University (Poland) winning it this year and solving all of the problems. The runner-up, Tsinghua University (China)
http://it.slashdot.org/article.pl?sid=07/03/19/0148220
Computer Programmers from Shanghai Jiaotong University in China Are World Champions -- Winners of the 29th Annual ACM International Collegiate Programming Contest, Sponsored By IBM
http://www.tmcnet.com/usubmit/2005/Apr/1131800.htm

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This year - the International Mathematical Olympiad 2007, Hanoi-Vietnam. (http://www.imo2007.edu.vn)

Who are winners? Congrats! This year, Russia is #1/93, the only team to win all golds (5)! China is #2/93, the only team to win all 4 golds (4).
Congrats to Vietnam to be #3/93 - the strongest in Asia Tenggara.
http://www.imo2007.edu.vn/index.php?...tByCountry.php

Malaysia is positioned #76/93 (never top 10)
Good try. Actually, these Malaysian participants are selected and good at maths in M'sia, than most of us.

Thailand - #14/93
Singapore - #36/93

In International Mathematical Olympiad, China team has been continuously in top 1 or 2 for than 10 years. Last year, China was #1, the only team to win all golds (5) in the 47th International Mathematical Olympiad, Slovenia 2006.