摘要：题目 给出一棵树，求出最小的k，使得，且在树中存在路径p，使得k =S且k include include include include include include const int maxlongint=2147483647; const int mo=1000000007; const 阅读全文

摘要：题目 Farmer John 正在在计划自己的农场漫步。他的农场的结构就像一棵树：农场有N个谷仓（1 include include include include include include const long long maxlongint=2147483647; using namesp 阅读全文

摘要：题目 给出一棵带边权的树，问有多少对点的距离 include include include include include include const long long maxlongint=2147483647; using namespace std; long long dis[12000 阅读全文