题目链接:https://vjudge.net/problem/HDU-4081 Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 8970    Accepted Submission(s): 3175 Problem Description During the…

Qin Shi Huang's National Road System                                                                   Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)                                                                …

Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 10567    Accepted Submission(s): 3727 题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4081 Description: During…

题目链接: Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)     Memory Limit: 32768/32768 K (Java/Others) Problem Description   During the Warring States Period of ancient China(476 BC to 221 BC), there were seven kingdoms in Ch…

枚举作为magic road的边,然后求出A/B. A/B得在大概O(1)的时间复杂度求出,关键是B,B是包含magic road的最小生成树. 这么求得: 先在原图求MST,边总和记为s,顺便求出MST上任意两点路径上的最长边d[i][j]. 当(u,v)是magic road时, 如果它在原本的MST上,则B就等于s-原(u,v)的权,而原(u,v)的权其实就是d[u][v]: 如果它不在原本的MST上,则B就等于s-d[u][v]+0. 总之就是一个式子:B=s-d[u][v]. 于是,在…

先发发牢骚:图论500题上说这题是最小生成树+DFS,网上搜题解也有人这么做.但是其实就是次小生成树.次小生成树完全当模版题.其中有一个小细节没注意,导致我几个小时一直在找错.有了模版要会用模版,然后慢慢融会贯通.我要走的路还长着啊. 这里有两个次小生成树的模版: http://www.cnblogs.com/Potato-lover/p/3949996.html 此题的解题思想:在prim算法中做一些改变,求出任意两点(u,v)路径之间的最大权值,并记录,记为maxe[u][v].运行一遍pr…

先求最小生成树 再遍历每一对顶点,如果该顶点之间的边属于最小生成树,则剪掉这对顶点在最小生成树里的最长路径 否则直接剪掉连接这对顶点的边~ 用prim算法求最小生成树最长路径的模板~ #include<cstdio> #include<cstring> #include<algorithm> #include<vector> #include<cmath> using namespace std; ; const int inf=1e9; dou…

Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3843    Accepted Submission(s): 1336 Problem Description During the Warring States Period of ancient China(47…

Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1287    Accepted Submission(s): 475 Problem Description During the Warring States Period of ancient China(47…

题目:Qin Shi Huang's National Road System Qin Shi Huang's National Road System Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 2049    Accepted Submission(s): 746 Problem Description During the W…