难度：2 前提：动态规划 后继： 资料： … 习题： SPOJ PT07Z. Longest path in a tree 树的直径 Codeforces Round AIM Tech Round 3 Problem C. Centroids HDU 2196. Computer HDU 5834. Magic boy Bi Luo with his excited tree http://user.qzone.qq.com/251815992/blog/1410720943 2014-2015 ACM-ICPC, Asia Mudanjiang Regional Contest, Probl……