摘要:
You are given a tree (an acyclic undirected connected graph) with N nodes, and edges numbered 1, 2, 3...N-1. We will ask you to perfrom some instructi 阅读全文
摘要:
题目描述 Farmer John has installed a new system of pipes to transport milk between the stalls in his barn (), conveniently numbered . Each pipe connects a 阅读全文