反之亦然

题目描述： City Horizon Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 19890 Accepted: 5499 DescriptionFarmer John has taken his cows on a trip to the city! As the sun sets, t...

D. Destruction of a Tree time limit per test1 second memory limit per test256 megabytes You are given a tree (a graph with n vertices and n - 1 edges in which it’s possible to reach any vertex from...