题目https://leetcode.cn/problems/maximum-employees-to-be-invited-to-a-meeting/description/题解从\(i\)向\(favorite[i]\)连边，会形成一张\(n\)个点\(n\)条边的有向图，且该图包含若干个连通块，每个连通块均为基环树，亦即该有向图为基环树森林。以测试用例[1,2,0]，进