First notebook entry: Introducing myself sports programing topcoder is site passed competetions. There is species several on top coder, algorithm, maraphon, mod dash, etc. Last main competetion 2010 years was conducted start in april and will end in begin august, finals was conducted in 11-14 october in a city las-vegas. Priz is 100 travel in las-vegas (for participation in finaly or for views) and 150 000 $. however mean priz is no many. Sponsors competention is yandex, paypal developer work, facebook, patron nsa (national security agency). The National Security Agency (NSA) is a world leader in the protection and exploitation of intelligence. This eccentrics are siting there and give offer better. Very popular is algorithm competetions. Every year in category are participate about 3000 people, for equals at activity member topcoder is 5000 people. Competetions is passing in several steps, at begginer three round qualification, next five online round before balance 24 finalists. Next final in las-vegas. Three algorithm task is different complexitying on 75 minutes plus on find errors other settings. Multiple champion Peter Mitrichev aka petr was losted at firs round that surpesed all. Top coder 2011 raund 4 Will Top coder 2011algorithm raund 4 do 23 july.