最短路问题此类问题类型不多,变形较少 POJ 2449 Remmarguts' Date(中等)http://acm.pku.edu.cn/JudgeOnline/problem?id=2449题意:经典问题:K短路解法:dijkstra+A*(rec),方法很多相关:http://acm.pku.edu.cn/JudgeOnline/showcontest?contest_id=1144该题亦放在搜索推荐题中 POJ 3013 - Big Christmas Tree(基础)http://ac…

非本人允许请勿转载. 趁热打铁,学会了邻接表把这个总结一下,以及感谢大佬uncle-lu!!!(奶一波)祝早日进队! 首先,图论入门就得是非常基础的东西,先考虑怎么把这个图读进去. 给定一个无向图,如下 怎么把这个图的数据读入进去呢? 把这个图剖析开来看,1连着的是2和3,2连着4和5,3连着6和7,4连着5,5连着8和6,6连着9. 所以这个图可以用一种神奇的东西----邻接矩阵来存.如下,能联通的制为1,不能联通的制为0. 那么可以看出来,这个邻接矩阵光读入的时间复杂度就是O(N2)的了,在…

Network Time Limit: 1000MS Memory Limit: 30000K Total Submissions: 14721 Accepted: 5777 Special Judge Description Andrew is working as system administrator and is planning to establish a new network in his company. There will be N hubs in the company…

POJ 3270 Cow Sorting 题意: 一个序列变为升序,操作为交换两个元素,代价为两元素之和,求最小代价 题解: 看了黑书... 首先循环因子分解 一个循环完成的最小代价要么是循环中最小元素依次与其他交换,要么引入全局最小值来交换 $sum+min(mn*(len-2),mn+Min*(len+1))$ #include<iostream> #include<cstdio> #include<cstring> #include<algorithm>…

Ombrophobic Bovines Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 16539 Accepted: 3605 Description FJ's cows really hate getting wet so much that the mere thought of getting caught in the rain makes them shake in their hooves. They have…

A Plug for UNIX Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 14786 Accepted: 4994 Description You are in charge of setting up the press room for the inaugural meeting of the United Nations Internet eXecutive (UNIX), which has an interna…

PIGS Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 18209 Accepted: 8277 Description Mirko works on a pig farm that consists of M locked pig-houses and Mirko can't unlock any pighouse because he doesn't have the keys. Customers come to th…

Play on Words Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 10620 Accepted: 3602 Description Some of the secret doors contain a very interesting word puzzle. The team of archaeologists has to solve it to open that doors. Because there is…

Drainage Ditches Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 62016 Accepted: 23808 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by wate…

由于我这个破题提交了十四五遍,所以我决定写篇博客来记录一下. 这个题的题目描述是这样的 首先一看这个题我瞬间就想到了一笔画问题(欧拉回路). 对于能够一笔画的图,我们有以下两个定理. 定理1:存在欧拉路的条件:图是连通的,有且只有2个奇点. 定理2:存在欧拉回路的条件:图是连通的,有0个奇点. 求欧拉路的算法很简单,使用深度优先遍历即可.时间复杂度O(m+n) #include<iostream> #include<cmath> using namespace std; ] ={}…