Description You are a butler in a large mansion. This mansion has so many rooms that they are merely referred to by number (room 0, 1, 2, 3, etc...). Your master is a particularly absent-minded lout and continually leaves doors open throughout a part…

题目链接 题意 : 庄园有很多房间,编号从0到n-1,能否找到一条路径经过所有开着的门,并且使得通过门之后就把门关上,关上的再也不打开,最后能回到编号为0的房间. 思路 : 这就是一个赤裸裸的判断欧拉通路的问题了,但实际上,就只有两种情况能够输出YES,以房间为顶点,连接房间之间的门为边构造图,这两种情况分别是存在欧拉回路和欧拉通路的情况:所有房间都是偶数个门并且起始房间就是0,所以可以回到0,存在欧拉回路:有两个房间的门是奇数个,其余都是偶数个,这种情况下,要求出发房间和0房间的门是奇数个,并…

题目链接:http://poj.org/problem?id=1300 You are a butler in a large mansion. This mansion has so many rooms that they are merely referred to by number (room 0, 1, 2, 3, etc...). Your master is a particularly absent-minded lout and continually leaves door…

Door Man Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 2596   Accepted: 1046 Description You are a butler in a large mansion. This mansion has so many rooms that they are merely referred to by number (room 0, 1, 2, 3, etc...). Your mas…

http://poj.org/problem?id=1300 要不是书上有翻译我估计要卡死,,,首先这是一个连通图,鬼知道是那句话表示出来的,终点必须是0,统计一下每个点的度数,如果是欧拉回路那么起点必须是0,因为起点等于终点. 如果是欧拉通路的话,起点必须不是0而且0的度数必须是奇数不然不满足欧拉图的定义. 还有就是输入很操蛋,用的stringstream. #include<iostream> #include<cstdio> #include<cstring> #…

题目链接: http://poj.org/problem?id=1300 Door Man Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 2137   Accepted: 857 Description You are a butler in a large mansion. This mansion has so many rooms that they are merely referred to by number…

题目大意:给定一捆木棒,每根木棒的每个端点涂有某种颜色.问:是否能将这些棒子首位项链,排成一条直线,且相邻两根棍子的连接处的颜色一样. 解题思路:此题是一道典型的判断欧拉回路或欧拉通路的问题,以木棍的端点颜色为顶点.方法是:先用并查集判断图是否连通,然后统计奇度顶点的个数sumj , 如果 sumj == 0 , 则图中存在欧拉回路 :如果 sumj == 2  , 则图中存在欧拉通路 : 如果 sumj > 2 ,则图中不存在欧拉通路.但是此题的关键是如何给端点颜色编号,一开始,我用map映射…

系统的学习一遍图论!从这篇博客开始! 先介绍一些概念. 无向图: G为连通的无向图,称经过G的每条边一次并且仅一次的路径为欧拉通路. 如果欧拉通路是回路(起点和终点相同),则称此回路为欧拉回路. 具有欧拉回路的无向图G称为欧拉图. 有向图: D为基图连通的有向图,则称经过D的每一条边并且仅一次的路径为有向欧拉通路. 如果该通路是回路,则称为有向欧拉回路. 具有有向欧拉回路的有向图D称为有向欧拉图. 无向图判断欧拉通路:G为连通图,且仅有两个奇度的节点或者无奇度节点. 如果有两个奇度的点,那么这两…

Description In order to get from one of the F (1 <= F <= 5,000) grazing fields (which are numbered 1..F) to another field, Bessie and the rest of the herd are forced to cross near the Tree of Rotten Apples. The cows are now tired of often being forc…

题目大意: 从0~n-1编号的房间,从一个起点开始最后到达0号房间,每经过一扇门就关上,问最后能否通过所有门且到达0号房间 我觉得这道题的输入输出格式是我第一次遇到,所以在sscanf上也看了很久 每一行对应当前门能到达的房间,下方如有重复不在输入,所以会有空行,这里的空行,和将字符串内的数字一个个代入需要好好斟酌 这里只有两种情况能成功 从 0号房间出发,经过一个欧拉回路到达0 从别的房间出发,一个欧拉通路到达0,2个端点的均为基度节点 代码: #include <iostream> #in…