题目大意: 曼哈顿最小距离生成树 算法讨论: 同上. 这回的模板真的准了. #include <iostream> #include <cstring> #include <cstdlib> #include <algorithm> #include <cstdio> using namespace std; + ; ; typedef long long ll; const ll oo = 100000000000000LL; int n, e…

http://poj.org/problem?id=3241 曼哈顿距离最小生成树模板题. 核心思想是把坐标系转3次,以及以横坐标为第一关键字,纵坐标为第二关键字排序后,从后往前扫.扫完一个点就把它插到树状数组的y-x位置上,权值为x+y.查询时查询扫过的所有点满足ydone-xdone>=ynow-xnow时,直接是树状数组中的的一个后缀区间,从后往前扫保证了区间内的这些点都在当前点的y轴向右扫45度的范围内.树状数组实现查询x+y的最小值,以及此最小值对应原数组中的位置,方便建图连边. 模板…

Minimum Spanning Tree Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) [Problem Description] XXX is very interested in algorithm. After learning the Prim algorithm and Kruskal algorithm of minimum spanning tree, XXX…

Problem Description XXX is very interested in algorithm. After learning the Prim algorithm and Kruskal algorithm of minimum spanning tree, XXX finds that there might be multiple solutions. Given an undirected weighted graph with n (1<=n<=100) vertex…

给定一个无向图,如果他的某个子图中,任意两个顶点都能互相连通并且是一棵树,那么这棵树就叫做生成树(spanning tree). 如果边上有权值,那么使得边权和最小的生成树叫做最小生成树(MST,Minimum Spanning Tree).       1.prim版本的算法   .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", co…

E. Minimum spanning tree for each edge   Connected undirected weighted graph without self-loops and multiple edges is given. Graph contains n vertices and m edges. For each edge (u, v) find the minimal possible weight of the spanning tree that contai…

E. Minimum spanning tree for each edge time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Connected undirected weighted graph without self-loops and multiple edges is given. Graph contains n …

E. Minimum spanning tree for each edge 题目连接: http://www.codeforces.com/contest/609/problem/E Description Connected undirected weighted graph without self-loops and multiple edges is given. Graph contains n vertices and m edges. For each edge (u, v) f…

You may refer to the main idea of MST in graph theory. http://en.wikipedia.org/wiki/Minimum_spanning_tree Here is my own interpretation What is Minimum Spanning Tree? Given a connected and undirected graph, a spanning tree of that graph is a subgraph…

这题本来是想放在educational round 3的题解里的,但觉得很有意思就单独拿出来写了 题目链接:609E - Minimum spanning tree for each edge 题目大意:n个点,m条边,对每条边,询问包含此边的最小生成树的边权之和 题解:大部分人都是用LCA写的,这里提供一个更为精妙的做法. 模拟Kruskal算法建MST的过程,先将m条边按边权排序,依次进行判断.若点对(u,v)属于同一个连通块,则加入边{u,v,w}后会形成一个环,把环中最大的边换成w会多产…