Rule of Ping-Pong Game:
Rotating contest among groups: There will be 21 round contests if 7 people per group. There will be 15 round contests if there are 6 people per group.
The sequence of group contest:
Semi-final: Only first two winners per group can enter semi-final contest. There will be 4 people to attend semi-final for two groups. The champion of the first group competes with the second-place of the second group. The second-place of the first group competes with the champion of second group. The winner will attend the final. The loser will be the 3-place.
Final: Final is based on the system of winning 3 out of 5 rounds. The winner will be the champion. The loser will be the second-place.