In other words, the last group left is the champion, and the twelve groups are the six-team competition group. After the first round, there will be six groups left. You can choose to draw lots or choose your opponents freely to decide the competition group, twelve into six, six into three, and the last three groups can compete in different ways, giving different scores a first place.
There are many ways to improve the competition mechanism. Fairness, impartiality and openness are required during the competition, and sometimes mistakes need to be adjusted in time.
The competition mechanism can set up some emergency plans, which can improve the competition mechanism and the whole competition.