题目链接 给一棵树, 每条边有权值, 两种操作, 一种是将一条边的权值改变, 一种是询问u到v路径上最大的边的权值. 树链剖分模板. #include <iostream> #include <vector> #include <cstdio> #include <cstring> #include <algorithm> #include <cmath> #include <map> #include <set&g…

思路 注意本题只能用C,不能用C++ 其他的都和上一题一样 代码 #include <stdio.h> #include <string.h> #define MAXN 10010 int dfs_clock,dep[MAXN*2],heason[MAXN*2],id[MAXN*2],sz[MAXN*2],top[MAXN*2],fa[MAXN*2],w_p[MAXN*2],v[MAXN*2],fir[MAXN*2],nxt[MAXN*2],w[MAXN*2],val[MAXN*2…

题目链接:传送门 题目大意:给一棵无根树,树边有权值,有很多次操作,QUERY代表询问从 x 到 y 路径上的边的最大 权值,CHANGE代表改变按输入顺序第 x 条边的权值为 y. 对于每个QUERY,输出一个答案. 题目思路:树链剖分(第一次学树链,还有点云里雾里的) #include <iostream> #include <cstdio> #include <cstdlib> #include <cmath> #include <algorit…

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 instructions of the following form: CHANGE i ti : change the cost of the i-th edge to tior QUERY a b : ask fo…

人生第一道树链剖分的题目,其实树链剖分并不是特别难. 思想就是把树剖成一些轻链和重链,轻链比较少可以直接修改,重链比较长,用线段树去维护. 貌似大家都是从这篇博客上学的. #include <cstdio> #include <cstring> #include <algorithm> #include <vector> using namespace std; + ; int n; int tot; vector<int> G[maxn]; i…

Query on a tree Time Limit: 5000ms Memory Limit: 262144KB   This problem will be judged on SPOJ. Original ID: QTREE64-bit integer IO format: %lld      Java class name: Main Prev Submit Status Statistics Discuss Next Font Size: + - Type:   None Graph…

SPOJ太慢了,SPOJ太慢了, 题意:给定n(n<=10000)个节点的树,每条边有边权,有两种操作:1.修改某条变的边权:2.查询u,v之间路径上的最大边权. 分析:树链剖分入门题,看这里:http://blog.sina.com.cn/s/blog_6974c8b20100zc61.html 轻重链剖分,线段树维护,复杂度 O(nlogn + q* logn * logn ) SPOJ太慢了,我知道我写的应该是没错了, 最后把自己宏定义的max和min去掉之后终于过了,傻逼笑呵呵了..为啥…

375. Query on a tree Problem code: QTREE 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 instructions of the following form: CHANGE i ti : change the cost of…

QTREE - Query on a tree #number-theory 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 instructions of the following form: CHANGE i ti : change the cost of t…

QTREE - Query on a tree #tree 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 instructions of the following form: CHANGE i ti : change the cost of the i-th e…