Columbia team to compete in ACM-ICPC World Finals in Beijing

Three Columbia computer science graduate students have qualified to compete in the 2018 world finals of the Association for Computing Machinery (ACM) International Collegiate Programming Contest (ICPC) to be held April 15 – 20 in Beijing. The ACM-ICPC, sometimes called the “Olympics of Programming,” is the oldest and largest programming contest in the world and one of the most prestigious.

The students qualifying are Peilin Zhong, Ying Sheng, Haomin Long who, together with their coach Chengyu Lin, are all veterans of previous programming contests, including previous attempts to advance to the ICPC world finals.

The team, under the name CodeMbia, advanced this year after competing in the Greater New York Regional competition held November 19, where 52 area teams (including two other Columbia teams) were given five hours to complete 10 complex programming problems. CodeMbia solved 8 of the 10 problems, enough to tie with a Cornell team for first place, sending both onto the world finals.

With 2,948 universities competing in regional contests around the world, 128 teams earned the right to advance to the final round. Columbia last won a regional round in 2010, when the team that year traveled to Harbin, China, and finished 36th in the world.

Like in other programming contests, the ICPC regional problems consist of well-known, general computational problems that teams are asked to adapt for a specific case. Shortest path for instance might be presented as a subway map where competitors must determine the shortest path between two points. (The problems for the Greater New York Regional are given here.)

But the ICPC is a programming contest with a twist: three team members share a single computer.

“Other contests only measure how good you are in solving problems,” says Lin. “But the ICPC also tests how good you are at collaborating and at communicating with your team mates. So we have to practice collaboration, and how to divide up tasks to make the best use of the computer.”

With one person at the computer, the other two concentrate either on solving the problem or looking for errors or bugs, printing out the code to visually inspect it. Says Lin, “We have to learn to use the computer when it makes the most sense. We think a lot about how to solve the problem and how to verify that the algorithm works before we start coding. Otherwise, just coding for an hour is a waste of time.”

Hardest part for the team? “Not making mistakes. As contest veterans, we had the advantage of being able to solve the problems faster, so could spend more time double-checking our work for mistakes or for problems in the algorithm itself.”

The world finals will follow a similar format as the regionals—10 problems in five hours—but the problems themselves will be harder. So the team is stepping up its practice sessions, switching from the relatively easy regional problems to the more difficult ones from past finals.

The competition will be harder also. Facing CodeMbia will be 127 other qualifying teams. Lin makes no predictions for how well the team will do in the finals, but he stresses the fun of programming and looks forward to the challenge of competing against the world’s best collegiate programmers.

The ICPC world finals takes place at Peking University April 15 – 20.

Posted 2/20/18
– Linda Crane