答案:选一个囚犯出来负责关灯,其余的负责开灯,而且每人只能开一次,当这个囚犯关够99次的时候,就知道所有的囚犯都来过院子了。tvb now,tvbnow,bttvb. A, [* N, `" ~/ F( K
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i don't get it.. how to pick someone to record it.. when there is only 1 person allow to go out each day..and he/she will lock up later |