“卓见杯”第五届CCPC中国大学生程序设计竞赛河南省赛网络赛 D Defending Plan Support（树形dp，贡献值，递推）

题目描述node The architectural structure of the college is strange, but the rule is that there is only one simple path between every two classrooms. Now the battle between Class A and Class F broke out. A

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