题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=3072 题目大意:为一个有向连通图加边.使得整个图全连通,有重边出现. 解题思路: 先用Tarjan把强连通分量缩点. 由于整个图肯定是连通的,所以枚举每一条边,记录到非0这个点所在连通分量的最小cost. 一共需要累加cnt-1个连通分量的cost. 在Tarjan过程中的重边,可以用链式前向星结构解决.(vector邻接表会算错) 在枚举每条边的cost中,用cost[i]记录i这个连通分量的最…

Intelligence System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 982    Accepted Submission(s): 440 Problem Description After a day, ALPCs finally complete their ultimate intelligence system,…

强连通分量——tarjin 算法 这道题和前面那道hdu 2767唯一不同就是,2767需要找出最小数量的边使图成为连通分量,而这个题需要一点点贪心的思想在里面,它需要求出代价最小的边使图成为连通分量: 代码: #include <cstdio> #include <cstring> #include <iostream> #include <stack> #define N 50006 using namespace std; struct Edge {…

Intelligence System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3414    Accepted Submission(s): 1494 Problem Description After a day, ALPCs finally complete their ultimate intelligence syste…

Intelligence System Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 32768/32768K (Java/Other) Total Submission(s) : 2   Accepted Submission(s) : 1 Font: Times New Roman | Verdana | Georgia Font Size: ← → Problem Description After a day, ALPCs…

Intelligence System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1650    Accepted Submission(s): 722 Problem Description After a day, ALPCs finally complete their ultimate intelligence syste…

题意: 给出一个N个节点的有向图.图中任意两点进行通信的代价为路径上的边权和.如果两个点能互相到达那么代价为0.问从点0开始向其余所有点通信的最小代价和.保证能向所有点通信. 题解: 求出所有的强连通分量,然后进行缩点操作.最后贪心的找出每个点的最小代价,然后求和. #include <iostream> #include <cstdio> #include <vector> #include <cstring> #include <algorithm…

题意,从0点出发,遍历所有点,遍历边时候要付出代价,在一个SCC中的边不要付费.求最小费用. 有向图缩点(无需建立新图,,n<=50000,建则超时),遍历边,若不在一个SCC中,用一个数组更新记录最小到达该连通分量的最小边权即可...边聊天,边1A,哈哈... #include<iostream> #include<stack> #include<queue> #include<cstdio> #include<cstring> usin…

给出一个带权有向图,要使整个图连通.SCC中的点之间花费为0,所以就先缩点,然后缩点后两点之间的权值为最小边的权值,把这些权值累加起来就是答案. #include <iostream> #include <cstdio> #include <algorithm> #include <cstring> #include <vector> #include <stack> using namespace std; int n, m; +…

Intelligence System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 2909    Accepted Submission(s): 1259 Problem Description After a day, ALPCs finally complete their ultimate intelligence syst…