北京师范大学第十四届ACM决赛 I Cactus Exploration 菊花图，仙人掌树

https://www.nowcoder.com/acm/contest/12/I

菊花图:

一个点，这个点与其他所有的点都连通。

来一个灵魂画师吧- - 

菊花图如果每一对与红色点相连的边都相互连，也就是形成一个环的话。

那么最多2*n-2条边，不能再多了。

那么能形成多少个环呢，m-n+1个环。

1.首先的条件，我的边起码得n-1条并且比2*n-2条边少。

2.当m=n的时候形成n边形，此时答案最大n*n

3.然后就得到最后的f(x)=x*(m-(m-n+1-1)*x)

x代表的意思是最小的环的长度，最后的答案一定是一个大环，然后其他全是小环，要不然可以把边加在这个大环里使

答案更大。所以f(x)的最大值为最后的答案，但首先还是要满足一些条件

1.最小的环长度至少是2

2.x<=m/(m-n+1)这个显然。

如果x=2则另x++

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