Widgets Magazine

CS team places 14th at World Finals

CS team members from left: Andy Nguyen (coach), Jeffrey Wang, Jaehyun Park and Phillip Krähenbühl compete in IBM’s international CS competition. The team placed 14th overall and was named North American champion. (Photo courtesy of Jaehyun Park)

A Stanford computer science team was named North American champion last weekend at the ACM International Collegiate Programming Contest (ACM-ICPC) World Finals in Harbin, China.

The team won 14th place overall.

The Stanford team of three was among about 22,000 contestants from 1,931 universities and 82 countries who competed in regional contests, according to team member Jaehyun Park ’12.

Park, Jeffrey Wang ’10 and first-year computer science graduate student Philipp Krähenbühl qualified to compete in Harbin after coming in second in the Pacific Northwest Regional preliminaries in November. The United States sent 18 other teams to compete against 84 other teams.

The team left California on Jan. 30 to compete in Harbin for a week, returning on Feb. 6. The team members missed a week of school to compete, rescheduling midterms to travel to sub-zero temperatures in northern China.

In the competition, teams were given five hours to solve challenging computer science problems individually. The team that solved the most problems in the least amount of time won.

“The problem can be anything computable and verifiable by computers,” Park explained in an e-mail. “The core of a problem is purely mathematical, but usually the problem setters hide it in a fun and interesting story.”

Park is no stranger to the world finals, having competed last year as a freshman in Stockholm, Sweden along with Wang and Andy Nguyen ’09. Nguyen is now the team’s coach.

“Compared to the last year’s world finals, this year’s problem set was a bit more ‘standard,’ and perhaps a bit more easily accessible,” Park said.

A team from Shanghai Jiaotong University came in first place, correctly solving seven problems, followed by Moscow State University and National Taiwan University in second and third, respectively.

Park said that he was half-surprised and half-disappointed by Stanford’s win as North American champion.

“During the first two hours, Stanford was in first place,” Park said. “We solved the problems really quickly and precisely. But then we were stuck and couldn’t get more problems, while other teams slowly took us over.”

The scoreboard, which freezes during the last hour of competition, indicated that Stanford was in fifth place. During the last hour, nine other teams solved more problems, pushing Stanford’s team ranking down to 14th.

“It was kind of sad considering our good performance at the beginning,” Park added. “But we were also startled to realize that no schools from North America did better than us.”

Stanford has won the World Championships three times in ACM-ICPC history, most recently in 1991. Last year, Stanford placed 20th; its team finished seventh in 2008. Next year’s World Finals are scheduled to be held in Cairo.