假定在一舞会上，男士排成一队，女士排成一队。跳舞开始时，依次从男队和女队的队头各出一人配成舞伴。若两队初始人数不相同，则较长的那一队中未配对者等待下一轮舞曲。-Assume that in a ball, lined up a team of men, women lined up a team. Dance begins, followed by men s and women s teams from the teams head out of one pair each partner. If the initial number of teams is not the same, the longer the team who did not wait for the next round of matching dance.