传送门 题意 给出一张n个点m条边的无向图,点的颜色为0/1,每次有两种操作: 1.Asksum x y,查询两点颜色为x和y的边的权值之和 2.Change x,将x颜色取反 分析 最直接的做法是每次改变点的颜色豆浆与该点所连的边更新,\(O(q*m)\),超时 那么我们考虑将点根据度数分类,将度数\(<sqrt(m)\)的点称为普通点,否则为超级点.设置sum[i][0/1]代表第i个点(超级点)与颜色为0/1相连的边的权值和.普通点颜色改变,暴力修改与普通点相连的所有的点对答案的贡献\(O…

HDU4467 Graph 题意: 给出一张染色图,\(n\)个点每个点是黑色或者白色,\(m\)条带权边,\(q\)次操作,有两种操作: 改变一个点的颜色 问所有边中两个端点的颜色为给定情况的边权和是多少 题解: 首先因为有重边,所以先把重边合并一下 然后按每个点的度数是否大于\(\sqrt{边总数}\),把点分轻点和重点,同时记录所有三种询问情况的答案 在图中,重点我们保存其所有连的重点的边,轻点我们保存其所有连出去的边 显然重点不会超过\(sqrt{边总数}\)个,且重点和轻点所连出去的边…

Graph Problem Description P. T. Tigris is a student currently studying graph theory. One day, when he was studying hard, GS appeared around the corner shyly and came up with a problem: Given a graph with n nodes and m undirected weighted edges, every…

TimeWall is a graph databases github It be used to apply mathematic model and social network with graph algorithms and so on... Features: 1. C/S structure 2. compute in memory 3. dynamic add and remove nodes on the graph db 4. with lots of algorithms…

Source: Connected Brain Figure above: Bullmore E, Sporns O. Complex brain networks: graph theoretical analysis of structural and functional systems.[J]. Nature Reviews Neuroscience, 2009, 10(3):186-198. Graph measures A graph G consisting of a set of…

Destroying The Graph Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 8198   Accepted: 2635   Special Judge Description Alice and Bob play the following game. First, Alice draws some directed graph with N vertices and M arcs. After that B…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected components in an undirected graph. Example 1: 0          3 |          | 1 --- 2    4 Given n = 5 and…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges make up a valid tree. For example: Given n = 5 and edges = [[0, 1], [0, 2], [0, 3], [1, 4]], return tru…

Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors. OJ's undirected graph serialization: Nodes are labeled uniquely. We use # as a separator for each node, and , as a separator for node label and each neigh…

Influence maximization on big social graph Fanju PPT链接: social influence booming of online social network 一, Application:viral marketing 1, identify influence customers: seeds. 2, convince them to adopter product. other application: Rumor monitoring…