题意:与poj3268一样,所有人需要从各点到一点再从一点到各点,求最短路总和. 与poj3268一样,先正向建图跑 dijkstra ,得到该点到其他所有各点的最短路,即这些人回去的最短路,再用反向建的图跑一遍最短路,得到各点到该点的最短路,求和就行了. #include<stdio.h> #include<string.h> #include<algorithm> #include<queue> #include<vector> using…

Invitation Cards Time Limit: 8000MS   Memory Limit: 262144K Total Submissions: 23357   Accepted: 7675 Description In the age of television, not many people attend theater performances. Antique Comedians of Malidinesia are aware of this fact. They wan…

求单源最短路到其余各点,然后返回源点的总最短路长,以构造邻接表的方法不同分为两种解法. POJ1511(ZOJ2008)-Invitation Cards 改变构造邻接表的方法后,分为两种解法 解法一: //POJ1511-ZOJ2008 //Time:7766Ms Memory:99112K //求从1处到各点后再返回1处的最短总路长 //需要构造邻接表和逆邻接表 //构造方法1:vector构造邻接表 //SPFA+邻接表 #include<iostream> #include<cs…

POJ1511 问你从1到其它点得所有最短路之和  与  其他点到1得所有最短路之和 得总和 思路很明确就是两次最短路,翻转一次地图就好了 一开始就是两次spfa之间处理好数据得更新管理就好 vector结构体数组存储边得数据 dis存储最短路径 vis表示i是否在队列中 id与cnt来链式前向星 需要仔细考虑得不仅仅是spfa算法了,而是开头和中间得跟新优化处理,该初始化的得初始化,初始化成什么值还得清楚 所以后来我就想用引用和数组指针来做,觉得得快一点吧,因为我用空间换了时间,新一个reed…

边取反,从汇点跑单源最短路即可. #include<cstdio> #include<cstring> #include<queue> #include<algorithm> using namespace std; #define MAXN 1111111 #define MAXM 1111111 inline void in(int &ret){ ; '); +c-',c=getchar(); } void out(long long x){ )…

转载请注明出处: http://www.cnblogs.com/fraud/          ——by fraud Invitation Cards Time Limit: 5 Seconds      Memory Limit: 65536 KB In the age of television, not many people attend theater performances. Antique Comedians of Malidinesia are aware of this fa…

<题目链接> 题目大意: 有向图,求从起点1到每个点的最短路然后再回到起点1的最短路之和. 解题分析: 在求每个点到1点的最短路径时,如果仅仅只是遍历每个点,对它们每一个都进行一次最短路算法,那么即使是用了堆优化的dijkstra,时间复杂度也高达$O(n^2log(n))$,而本题有1000000个点,毫无疑问,这种想法必然是不可行的,所以我们可以采用逆向思维,将图中的每一条有向边全部反向,然后以1为起点,仅做一次dijkstra,就能得到1到所有点的最短距离,即反向前的,所有点到1点的最短…

Description In the age of television, not many people attend theater performances. Antique Comedians of Malidinesia are aware of this fact. They want to propagate theater and, most of all, Antique Comedies. They have printed invitation cards with all…

Invitation Cards Time Limit: 8000MS   Memory Limit: 262144K Total Submissions: 34743   Accepted: 11481 题目链接:http://poj.org/problem?id=1511 Description: In the age of television, not many people attend theater performances. Antique Comedians of Malidi…

题目链接:http://poj.org/problem?id=1511 Invitation Cards Time Limit: 8000MS   Memory Limit: 262144K Total Submissions: 29286   Accepted: 9788 Description In the age of television, not many people attend theater performances. Antique Comedians of Malidine…