USACO

The United States of America Computing Olympiad (USACO) is a computer programming competition for secondary school students in the United States. The USACO offers six competitions during the academic year for students at four increasingly difficult levels: Bronze, Silver, Gold and Platinum. Participants in the USACO submit programs in one of five languages: C, C++, Java, Pascal, and Python. Participants advance through the levels by performing well in their current division. A week-long summer training camp is held where four students are selected from a group of 24 finalists to represent the United States at the International Olympiad in Informatics (IOI). All expenses are paid for the training camp and competition at IOI. The USACO was founded in 1992 by Don Piele at the University of Wisconsin-Parkside and is currently maintained by director Brian Dean at Clemson University and a dedicated volunteer coaching staff.

The USACO contains several training pages on its website which are designed to develop one's skills in programming solutions to difficult and varied algorithmic problems at one's own pace. In addition to around 100 problems, there are texts on programming techniques such as greedy algorithms, dynamic programming, shortest path, and many others. Enthusiasts find the training pages so useful that people from other countries use them to prepare for their own national Olympiads; those from other countries in fact outnumber U.S. participants.

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