By drawing lots, the first round of 1 bye is set. Generally, the number 1 or 7 is set to bye. Take bye on the 7th as an example. Six other people draw lots according to the number of 1-6, and three people win. 1 and 2 dozen, 3 and 4 dozen ... 1 and 2 winners and 3 and 4 winners, 5 and 6 winners against No.7; Then decide the finalists and champions.