Description Little Johnny has got a new car. He decided to drive around the town to visit his friends. Johnny wanted to visit all his friends, but there was many of them. In each street he had one friend. He started thinking how to make his trip as s…

题目链接:http://poj.org/problem?id=1041 思路:懒得写了,直接copy吧:对于一个图可以从一个顶点沿着边走下去,每个边只走一次,所有的边都经过后回到原点的路.一个无向图存在欧拉回路的充要条件是每个顶点的度是偶数, 对于有向图存在欧拉回路的条件是每个顶点的出度等于入度(就是出去的边数等于进来的边数).根据这个首先判断存在欧拉回路不, 如果存在然后用DFS去找欧拉回路.DFS的思想等效于先找一个环,然后对环上所有点递归DFS,并且把这些递归产生的路插入这个环中. 实际上…

[题目链接] http://poj.org/problem?id=1041 [算法] 欧拉回路[代码] #include <algorithm> #include <bitset> #include <cctype> #include <cerrno> #include <clocale> #include <cmath> #include <complex> #include <cstdio> #includ…

题目:http://poj.org/problem?id=1041 明明是欧拉回路字典序输出的模板. 优先队列存边有毒.写跪.学习学习TJ发现只要按边权从大到小排序连边就能正常用邻接表了! 还有一种存边的方法是把边的标号放到数组第二维里,达到一个桶的效果. 我当然知道那种模板是先dfs再在return的时候把边加进栈里最后倒序输出,可是这题为什么不正序呢? 然后WA了.发现可能先把一个点的度走完但此时其他点还有度这样的. 于是有了flag和return.然后就超时了. 再看看TJ,突然就明白了为…

Description From the article Number Theory in the 1994 Microsoft Encarta: ``If a, b, c are integers such that a = bc, a is called a multiple of b or of c, and b or c is called a divisor or factor of a. If c is not 1/-1, b is called a proper divisor o…

Description The GX Light Pipeline Company started to prepare bent pipes for the new transgalactic light pipeline. During the design phase of the new pipe shape the company ran into the problem of determining how far the light can reach inside each co…

Description You, as a member of a development team for a new spell checking program, are to write a module that will check the correctness of given words using a known dictionary of all correct words in all their forms. If the word is absent in the d…

Description New convocation of The Fool Land's Parliament consists of N delegates. According to the present regulation delegates should be divided into disjoint groups of different sizes and every day each group has to send one delegate to the concil…

Description Standard web browsers contain features to move backward and forward among the pages recently visited. One way to implement these features is to use two stacks to keep track of the pages that can be reached by moving backward and forward.…

题目链接 求给出的图是否存在欧拉回路并输出路径, 从1这个点开始, 输出时按边的升序输出. 将每个点的边排序一下就可以. #include <iostream> #include <vector> #include <cstdio> #include <cstring> #include <algorithm> #include <cmath> #include <map> #include <set> #in…