There will be a table tennis doubles competition in our class, and 20 people will take part. If the elimination system is adopted, how should I compile the competition table?

First draw lots and divide into ten groups, and then play the first round of pairwise competition. * * * Five groups won, advanced and five groups eliminated.

Then the second round can be held, one group can advance directly, and then the remaining four groups will compete to decide the winners of the two groups to enter the next round.

Then this round, three teams play round robin, each team plays twice. If a team wins two games, it will be the champion.

If there are two groups with one win and one loss, you can play another round or compare the record of this round, that is, the score is smaller.