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不一定,这题挺麻烦,主要是有一种特殊的情况...

Posted by dynamic at 2003-10-31 22:02:51 on Problem 1506
In Reply To:testdata错了吧? Posted by:xiaomi at 2003-10-31 21:33:33
这题其实是类似一个拓扑排序,但题目没要求拓扑排序唯一,只要求能够唯一解码
比方说,一个4个点的有向图,边为
(1,2),(1,3),(2,4),(3,4)
那么1和4的拓扑序是唯一的,而2和3的拓扑序不定
这时,如果题目的encrypted message只包含1,4,不包含2,3的话,按照题目的意思应该是可以唯一解码的。
至少我是这么理解这个题目的

但这样我就不会做了,还没想到好算法...

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