有n个选手 P 1 ,P 2 ,P 3 ,… ,P n 参加了的单循环赛，每对选手之间非胜即负。现要求求出一个选手序列 P 1 ,P 2 ,P 3 ,… ,P n , 使其满足 P i 胜 P i+ 1 (i=1,… ,n-1) 。-There are n players of P 1, P 2, P 3, ..., P n participated in a single round robin, each of the players that is negative between the non-wins. Players are now required to obtain a sequence P 1, P 2, P 3, ..., P n, to meet P i wins P i+ 1 (i = 1, ..., n-1).