Floraqiu的博客

【启发式合并】（dsu on tree）讲解+例题超级好的讲解（来自cf）1、启发式合并的作用：With dsu on tree we can answer queries of this type:How many vertices in the subtree of vertex v has some property in O(nlogn) time (for all of the...

例题一 Lomsat gelral CodeForces - 600EYou are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour.Let’s call colour c dominating in the subtree of vertex v if there are n...

Key Point:相等关系：可传递的，使用并查集进行检验不等关系：不可传递，使用set进行检验（如 X1 != X2 X1 != X3 但是X2 = X3 是可以成立的）数据分割 HDU - 6109小w来到百度之星的赛场上，准备开始实现一个程序自动分析系统。这个程序接受一些形如xi=xj 或 xi≠xj的相等/不等约束条件作为输入，判定是否可以通过给每个 w 赋适当的值...