Codefroces 1328E Tree Querie 题目 给出一棵1为根,n个节点的树,每次询问\(k_i\) 个节点,问是否存在这样一条路径: 从根出发,且每个节点在这条路径上或者距离路径的距离为1 题解 由于是从根出发的路径,所以 距离这条路径的距离为1=这个点的父亲在路径上 本身就在根出发的这条路径上,当然这个点的父亲也在路径上 这样我们就把两个条件统一了,转化问题为: 是否存在一条从根出发的路径,使所有点都在这条路径上 根据从根出发的路径的特点,我们根据深度,从小到大排序,每次看后…

题目大概说给一棵树,进行以下3个操作:把某结点为根的子树中各个结点值设为1.把某结点以及其各个祖先值设为0.询问某结点的值. 对于第一个操作就是经典的DFS序+线段树了.而对于第二个操作,考虑再维护一个域表示各个结点为根的子树是否有进行第二个操作,如果有那么该结点应该就要是0:而在进行第一个操作前,看一下子树是否有进行第二个操作,如果有就整个标记成没有并把标记上传,让该结点的父亲结点标记成进行了第二个操作. #include<cstdio> #include<cstring> #i…

题目大概说给一棵树,树上结点都有颜色(1到60),进行下面两个操作:把某结点为根的子树染成某一颜色.询问某结点为根的子树有多少种颜色. 子树,显然DFS序,把子树结点映射到连续的区间.而注意到颜色60种,这样就可以用一个64位整型去表示颜色的集合,然后就是在这个连续区间中用线段树成段更新颜色集合和区间查询颜色集合了. #include<cstdio> #include<cstring> using namespace std; #define MAXN 500000 struct…

D. Tree Requests time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Roman planted a tree consisting of n vertices. Each vertex contains a lowercase English letter. Vertex 1 is the root of the…

题目,是对一颗树,单点修改.子树查询.典型的dfs序入门题. DFS序可以将一颗树与子树们表示为一个连续的区间,然后用线段树来维护:感觉算是树链剖分的一种吧,和轻重链剖分不同的是这是对子树进行剖分的. 我用非递归方式求DFS序. #include<cstdio> #include<cstring> #include<algorithm> using namespace std; #define MAXN 111111 struct Edge{ int v,nxt; }e…

题目链接 Apple Tree Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 9692 Accepted: 3217 Description Wshxzt is a lovely girl. She likes apple very much. One day HX takes her to an apple tree. There are N nodes in the tree. Each node has an amou…

Apple Tree Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 36442   Accepted: 10894 Description There is an apple tree outside of kaka's house. Every autumn, a lot of apples will grow in the tree. Kaka likes apple very much, so he has bee…

http://codeforces.com/problemset/problem/570/D Tree Requests time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Roman planted a tree consisting of n vertices. Each vertex contains a lowercase…

题目描述 You are given a node-labeled rooted tree with n nodes. Define the query (x, k): Find the node whose label is k-th largest in the subtree of the node x. Assume no two nodes have the same labels. 输入 The first line contains one integer n (1 <= n <…

Mad scientist Mike has constructed a rooted tree, which consists of n vertices. Each vertex is a reservoir which can be either empty or filled with water. The vertices of the tree are numbered from 1 to n with the root at vertex 1. For each vertex, t…