[CC-BLREDSET]Black and Red vertices of Tree 题目大意: 有一棵\(n(\sum n\le10^6)\)个结点的树,每个结点有一种颜色(红色.黑色.白色).删去一个由红色点构成的连通块,使得存在一个黑点和一个白点,满足这两个点不连通.问有多少种删法. 思路: 设满足删掉这个点后,使得存在一个黑点和一个白点,满足这两个点不连通的红点为关键点.那么我们可以用两个\(\mathcal O(n)\)的树形DP求出所有的关键点.剩下的问题就变成了求有多少种全红连通…
Red/Blue Spanning Tree Time Limit: 2000ms Memory Limit: 131072KB This problem will be judged on HDU. Original ID: 426364-bit integer IO format: %I64d Java class name: Main Given an undirected, unweighted, connected graph, where each edge is co…
BaoBao has just found a rooted tree with n vertices and (n-1) weighted edges in his backyard. Among the vertices, of them are red, while the others are black. The root of the tree is vertex 1 and it's a red vertex.Let's define the cost of a red verte…
题目描述 BaoBao has just found a rooted tree with n vertices and (n-1) weighted edges in his backyard. Among the vertices, m of them are red, while the others are black. The root of the tree is vertex 1 and it’s a red vertex.Let’s define the cost of a re…
Given an undirected tree consisting of n vertices numbered from 0 to n-1, which has some apples in their vertices. You spend 1 second to walk over one edge of the tree. Return the minimum time in seconds you have to spend in order to collect all appl…
Ilya is very fond of graphs, especially trees. During his last trip to the forest Ilya found a very interesting tree rooted at vertex 1. There is an integer number written on each vertex of the tree; the number written on vertex i is equal to ai. Ily…
Ilya is very fond of graphs, especially trees. During his last trip to the forest Ilya found a very interesting tree rooted at vertex 1. There is an integer number written on each vertex of the tree; the number written on vertex i is equal to ai. Ily…
C. Bear and Forgotten Tree 3 题目连接: http://www.codeforces.com/contest/658/problem/C Description A tree is a connected undirected graph consisting of n vertices and n - 1 edges. Vertices are numbered 1 through n. Limak is a little polar bear and Rade…
B. Bear and Forgotten Tree 3 time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output A tree is a connected undirected graph consisting of n vertices and n - 1 edges. Vertices are numbered 1 through…
地址:http://codeforces.com/contest/842/problem/C 题目: C. Ilya And The Tree time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Ilya is very fond of graphs, especially trees. During his last trip…
Bear and Forgotten Tree 3 time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A tree is a connected undirected graph consisting of n vertices and n - 1 edges. Vertices are numbered 1 through…
题目链接: C. Bear and Forgotten Tree 3 time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A tree is a connected undirected graph consisting of n vertices and n - 1 edges. Vertices are numbered …
C. Bear and Forgotten Tree 3 time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A tree is a connected undirected graph consisting of n vertices and n - 1 edges. Vertices are numbered 1 thro…
转自:http://blog.csdn.net/shahdza/article/details/7779230 [HDU]1213 How Many Tables 基础并查集★1272 小希的迷宫 基础并查集★1325&&poj1308 Is It A Tree? 基础并查集★1856 More is better 基础并查集★1102 Constructing Roads 基础最小生成树★1232 畅通工程 基础并查集★2120 Ice_cream's world I 基础并查集★212…
原文转自:http://blog.ynada.com/303 I’ve plotted several word association graphs for this New York Times article (1st paragraph) using Rand the igraph library. #1, random method #2, circle method #3, sphere method #4, spring method #5, fruchterman-reingol…
Lab 11 System Rescue and Troubleshooting Goal: To build skills in system rescue procedures. Estimated Duration: 2 hours Lab Setup: When using rescue mode on a Xen enabled system, you may be prompted to select which root partition to mount. If you are…
A. Kirill And The Game time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Kirill plays a new computer game. He came to the potion store where he can buy any potion. Each potion is characteriz…
