Til the Cows Come Home Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly as possible.…

题目连接: http://poj.org/problem?id=2387 Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get ba…

题目链接:http://poj.org/problem?id=2387 题目大意:起点一定是1,终点给出,然后求出1到所给点的最短路径. 注意的是先输入边,在输入的顶点数,不要弄反哦~~~ #include <iostream> #include <cstdio> using namespace std; ][],Min,node[],vis[],t,q; ; void set() { ; i<=; i++) { node[i]=INF; vis[i]=; ; j<=;…

传送门:http://poj.org/problem?id=2387 题目大意: 给定无向图,要求输出从点n到点1的最短路径. 注意有重边,要取最小的. 水题..对于无向图,从1到n和n到1是一样的. 直接Dijkstra即可 #include<cstdio> #include<cstring> const int MAXN=1000+10; const int INF=999999; int map[MAXN][MAXN]; int dis[MAXN]; int main() {…

题目:从节点N到节点1的求最短路径. 分析:这道题陷阱比较多,首先是输入的数据,第一个是表示路径条数,第二个是表示节点数量,在 这里WA了四次.再有就是多重边,要取最小值.最后就是路径的长度的最大值不是100,而是100001.用Dijkstra求最短路径,感觉 Dijkstra和Prim很像,都是从结点中找到路径最小的一条,然后再做某种更新.Dijkstra是看看源节点通过当前节点能否缩短从源头到其他节 点的路径,而Prim则是通过加入当前节点到生成树,然后更新生成树中的路径数量,再从中找到最…

POJ 2387 Til the Cows Come Home (图论,最短路径) Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to g…

POJ.2387 Til the Cows Come Home (SPFA) 题意分析 首先给出T和N,T代表边的数量,N代表图中点的数量 图中边是双向边,并不清楚是否有重边,我按有重边写的. 直接跑spfa,dij,floyd都可以. 求1到N的最短路. 代码总览 #include <cstdio> #include <cstring> #include <algorithm> #include <queue> #include <stack>…

题目链接:http://poj.org/problem?id=2387 Til the Cows Come Home Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 45414   Accepted: 15405 Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible…

Dijkstra模板题,也可以用Floyd算法. 关于Dijkstra算法有两种写法,只有一点细节不同,思想是一样的. 写法1: #include <iostream> #include <cstdio> #include <cstring> #include <cmath> #include <algorithm> #define Mod 1000000007 using namespace std; #define N 1007 int mp…

传送门 Til the Cows Come Home Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 46727   Accepted: 15899 Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for…

Til the Cows Come Home Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 33015   Accepted: 11174 Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the…

Til the Cows Come Home 题目链接: http://acm.hust.edu.cn/vjudge/contest/66569#problem/A Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie…

Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly as possible. Farmer Joh…

Til the Cows Come Home Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly…

原题链接:Til the Cows Come Home 题目大意:有  个点,给出从  点到  点的距离并且  和  是互相可以抵达的,问从  到  的最短距离. 题目分析:这是一道典型的最短路径模版题,需要注意的是:使用dijkstra算法求解需要考虑有重复边问题,而使用bellman-ford算法 和 spfa算法 可以忽略这个问题. 代码如下: // Dijkstra #include <iostream> using namespace std; const int INTFY = 1…

题目链接:http://poj.org/problem?id=2387 题目大意:给你t条边(无向图),n个顶点,让你求点1到点n的最短距离. 解题思路:裸的dijsktra,注意判重边. 代码: #include<cstdio> #include<cmath> #include<cctype> #include<cstring> #include<iostream> #include<algorithm> #include<v…

Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly as possible. Farmer Joh…

题目 #define _CRT_SECURE_NO_WARNINGS #include<string.h> #include<stdio.h> #include<math.h> ; #define typec int const typec INF=0x3f3f3f3f;//防止后面溢出,这个不能太大 bool vis[MAXN]; int pre[MAXN]; typec cost[MAXN][MAXN]; typec lowcost[MAXN]; void Dijk…

Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly as possible. Farmer John's field ha…

题目链接:http://poj.org/problem?id=2387 题意:有n个城市点,m条边,求n到1的最短路径.n<=1000; m<=2000 就是一个标准的最短路模板. #include<iostream> #include<algorithm> #include<cstring> #include<vector> #include<queue> using namespace std; ; const int INF =…

Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie needs her beauty sleep, so she wants to get back as quickly as possible. Farmer John's field ha…

求1到N的最短路 注意有重边 跑一遍dijkstra就行 /* *********************************************** Author :Sun Yuefeng Created Time :2016/10/22 14:18:06 File Name :A.cpp ************************************************ */ #include<cstdio> #include<iostream> #inc…

(￣▽￣)" //dijkstra算法: //这题建邻接矩阵的时候有坑(先读入边后读入点),还有重边: #include<iostream> #include<cstdio> using namespace std; const int INF=10e7; ; int k,minn; int cost[MAXN][MAXN]; int lowcost[MAXN]; bool vis[MAXN]; void dij(int n,int start) { ;i<=n;i…

Time Limit: 1000MSMemory Limit: 65536K Total Submissions: 59755Accepted: 20336 Description Bessie is out in the field and wants to get back to the barn to get as much sleep as possible before Farmer John wakes her for the morning milking. Bessie need…

从点N到1的最短路 *记得无向图两个方向都要建边就好了…… 以及多组数据= = #include <iostream> #include <cstdio> #include <cstring> #include <queue> using namespace std; #define SZ 4005 #define INF 1e9+10 ; struct edge { int t,d; }l[SZ]; void build(int f,int t,int d…

题目链接:https://vjudge.net/problem/HDU-2544 题意: 题目要求找到节点1到节点n之间的一条最短路 分析: Dijkstra模板题 单源最短路径,可以用dijkstra(当然Floyd或者其他也可以),首先初始化节点间距离数组map和访问记录数组vis,然后录入并存储当前已知点间距离,再使用dijsktra算法以起始点为中心向外层层扩展(广度优先搜索思想),不断更新最短距离,直到扩展到终点为止.最后得到的dis[n]即为起点1至终点n的最短距离. 代码如下: #…

题意: 有N个点,给出从a点到b点的距离,当然a和b是互相可以抵达的,问从1到n的最短距离 分析: 典型的模板题,但是一定要注意有重边,因此需要对输入数据加以判断,保存较短的边,这样才能正确使用模板. 题解 #include<iostream> #include<Queue> #include<cstdio> #include<vector> #include<string.h> using namespace std; #define maxn…

hdu 2544  求点1到点n的最短路  无向图 Sample Input2 1 //结点数 边数1 2 3 //u v w3 31 2 52 3 53 1 20 0 Sample Output32 堆优化Dijstra模板 # include <iostream> # include <cstdio> # include <cstring> # include <algorithm> # include <cmath> # include &…

The Perfect Stall Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 20874   Accepted: 9421 Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering pr…

传送门:http://poj.org/problem?id=1655 题意:有T组数据,求出每组数据所构成的树的重心,输出这个树的重心的编号,并且输出重心删除后得到的最大子树的节点个数,如果个数相同,取编号小 的 思路:树的重心的模板题 首先要知道什么是树的重心,树的重心定义为:找到一个点,其所有的子树中最大的子树节点数最少,那么这个点就是这棵树的重心,删去重心后,生成的多棵树尽可能平衡.   所以寻找重心,即是最小化重心的最大子树.子树大小的计算分为两部分 的下面的子树大小,即可计算出 的上面…