A contestant debugs his robot during the qualification trials of the 21st International Robot Olympiad (IRO) at the International Convention Centre of Qingdao, east China's Shangdong Province, July 19, 2019. Some 200 contestants took part in the contest Friday. The winners will participate in the finals of China. (Xinhua/Li Ziheng)

Contestants attend the robot competition during the qualification trials of the 21st International Robot Olympiad (IRO) at the International Convention Centre of Qingdao, east China's Shangdong Province, July 19, 2019. Some 200 contestants took part in the contest Friday. The winners will participate in the finals of China. (Xinhua/Li Ziheng)

A contestant writes programs during the qualification trials of the 21st International Robot Olympiad (IRO) at the International Convention Centre of Qingdao, east China's Shangdong Province, July 19, 2019. Some 200 contestants took part in the contest Friday. The winners will participate in the finals of China. (Xinhua/Li Ziheng)