摘要：
Zhu and 772002 Problem Description Zhu and 772002 are both good at math. One day, Zhu wants to test the ability of 772002, so he asks 772002 to solve 阅读全文
摘要：
E. Cactus A connected undirected graph is called a vertex cactus, if each vertex of this graph belongs to at most one simple cycle. A simple cycle in 阅读全文