More than 80 people drew lots at the scene.

This depends on the number of participants. Generally less than 20 people, 5 rounds. Of course, if the number is small, don't use integral loop, you can loop directly;

Seven rounds under 40 people, nine rounds under 60 people, many people 1 1 round, many people1round;

This is also a universal standard. This round can be "played through", which means that high-level players can meet each other, and the final results show that the ranking is quite impressive.

Of course, how many rounds are used depends on many factors such as time, venue, chess set, chess clock, number of referees, arrangement conditions and so on. If there are some restrictions, we can adopt the competition system of grouping first and then eliminating, just like the competition in Country Garden. Of course, the seed players can also be divided into different groups according to their previous achievements.

In addition, there is a good form of competition, which is the double-loss elimination system. In other words, all players will be drawn together. It doesn't matter if they lose a set, they will enter the loser group, and the winner is king. In this way, if each group of players play again, those who lose two sets (or four sets) will be eliminated, and those who fail to reach this number will continue to play until the outcome is decided, and the two first will compete for the final championship.