Serpentine system
The Serpentine system is a method employed in the organization of a competition to define the seeded teams and arrange them in pools. The n ranked teams that will be involved in the tournament are distributed in m pools according to the following algorithm:
| Pool 1 | Pool 2 | ... | Pool m-1 | Pool m |
|---|---|---|---|---|
| 1 | 2 | ... | m-1 | m |
| 2m | 2m-1 | ... | m+2 | m+1 |
| 2m+1 | 2m+2 | ... | 3m-1 | 3m |
| ... |
For instance, 12 teams would be organized in four-team pools, according to the serpentine system, as follows:
| Pool 1 | Pool 2 | Pool 3 |
|---|---|---|
| 1 | 2 | 3 |
| 6 | 5 | 4 |
| 7 | 8 | 9 |
| 12 | 11 | 10 |
To improve competitivity, this method is sometimes used in conjunction with the drawing of lots method: the serpentine system is used only for some of the teams involved in a competition ("seeds"); the rest is distributed in pools following a drawing of lots.