题目网址: http://www.puzzleup.com/2018/
http://www.puzzleup.com/2018/puzzle/?12
答题时限: １０月18日７ＰＭ－比赛结束（约12月12日）
加分时限: １０月18日７ＰＭ－１０月24日６：５９ＰＭ
答对可得基本分１００分。答案可上传５次，每改１次答案从基本分扣２０分。
比赛期间内可随时上传答案，加分时限内答对第ｎ天加（６－ｎ）分
另依题目的难易有额外加分（如有８０％的人这题答错，答对者加８０分）
◆THE TELEPHONE GAME
2 people sit on a round table to play a variation of the telephone game.
They are numbered from 1 to 12 in clockwise order, i.e. the people with
adjacent numbers (including 1 and 12) sit next to each other. Person #1
chooses a secret word and starts the game by randomly selecting one of
the two neighbors and whispering the word to that person. Upon hearing
the word, each person continues the game by randomly selecting one of
the neighbors and whispering the word. The game ends when everyone knows
the secret word.
What is the probability that the last person whispering the word is
numbered 6?
Enter your answer as a reduced fraction. Example: 123/4567
12个人绕着圆桌坐着，开始玩一种变形的传话游戏。玩家们依顺时钟方向编号成
1至12号，号码相邻(包括1号与12号)的玩家座位相邻。游戏开始由1号玩家想出一
个密语，然后随机从其两位邻居中挑选一位，将密语悄稍地告知那个人。每个人
听到密语后，一样随机从其两位邻居中挑选一位，并悄稍告知密语。游戏会在每
位玩家都知道密语后结束。
问最后一个传达密语的玩家为6号玩家之机率？
以最简分数回答，如 123/4567。
译注：原文写2 people，看题意应该为12 people。