Hello, the following is a detailed explanation: the single round robin system is a single round robin competition between participating teams. (1) Calculation formula of single round robin tournament: tournament = number of teams (number of teams-1)/2 (2) Calculation method of single round robin tournament: when the number of teams is odd, the tournament is equal to the number of teams; When the number of two teams is equal, the number of rounds is equal to the number of two teams minus 1. (3) Arrangement method of single round robin: ① General arrangement method. Use "counter-clockwise rotation method" to arrange, first use Arabic numerals as code names, not team names. Divide the number of teams into equal sides according to the U-shaped trend. In the case of odd-numbered teams, the last digit plus 0 becomes an even number. In the first round, as long as a horizontal line is drawn between the opposing U-shaped teams, it is the order of the first round. In the second round, the number 1 in the upper left corner is fixed, and the rest of the numbers move one position counterclockwise, which is the order of the second round, and so on in subsequent rounds. In case of team O, the team will have a bye. For example, there are seven teams participating in the competition. The competition order is as follows: the first round, the second round, the third round, the fourth round, the fifth round, the sixth round and the seventh round1-61-41-31-22-70. The advantages of the counter-clockwise rotation method of—36—25—04—74—53—42—30—27—06—75—6 are that the competition progress of the participating teams is consistent, the arrangement method is simple, and it is easy to operate and check. However, when there are more than five teams in the odd number, the team with the second lowest will play against the team in the last round, such as the team represented by the above number 6. This has caused unfair competition in ball games. In order to solve this problem, most of the current competitions adopt the "Berger arrangement method". I hope I can help you! Ha ha laugh