2020-2021:teams:running_chicken:1 [CVBB ACM Team]

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2020-2021:teams:running_chicken:1 [CVBB ACM Team]

2020-2021:teams:running_chicken:1

1.题意

给$n$个人和$m_1$、$m_2$个数对，每一些这些数对对应一组匹配。求有多少种不同的排列，使得按这个排列交换顺序后这两次不同原来为匹配的数对交换后依然是匹配的。

2.小思路

大概注意要建图，按红蓝两种不同颜色建图，后面的讨论就比较简单了。

组合题最重要的一部，建立模型，转换题目

2020-2021/teams/running_chicken/1.txt · 最后更改: 2020/05/08 22:25 由 chenjiyuan3