有n个人围成一圈，顺序排号。从第一个人开始报数（从1到3报数），凡报到3的人退出 圈子，问最后留下的是原来第几号的那位。...

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有n个人围成一圈，顺序排号。从第一个人开始报数（从1到3报数），凡报到3的人退出 　　　圈子，问最后留下的是原来第几号的那位。 -Have n individuals form a circle, in that order排号. From the first person to start off (from the reported number of 1-3), who reported 3 people out of the circle, the final question left is the original issue of who the first few.