摘要：
题面:https://www.luogu.org/problem/P2607 cpp 没有上司的舞会+环套树(破环为链)。。。 Code: include include include include include include include include using namespace 阅读全文
摘要：
题面:https://www.luogu.org/problem/P1600 cpp V1[x] : 以x为LCA的路径的起点的集合。 Spn[x]: 以x为路径起点的路径条数。 V2[x]: 以x为终点的路径的起点集合。 V3[x]: 以x为LCA的路径的终点的集合。 s[x]:以x为终点的路径起 阅读全文