题解 CF55D :数位DP+数论
这题做了半天。美丽的数的定义是“可以被自己的所有非零数位整除的数”。做数位DP,想的就是每个状态需要什么参量来表示。注意到这个定义的限制并不在选取每个数位的时候,而是... Read more
这题做了半天。美丽的数的定义是“可以被自己的所有非零数位整除的数”。做数位DP,想的就是每个状态需要什么参量来表示。注意到这个定义的限制并不在选取每个数位的时候,而是... Read more
很显然是数位DP了。 Read more
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