Is It A Tree? Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 33083 Accepted Submission(s): 7574 题目链接 http://acm.hdu.edu.cn/showproblem.php?pid=1325 Problem Description A tree is a well-known data…

一开始以为两道题是一样的,POJ的过了直接用相同代码把HDU的交了,结果就悲剧了.最后发现HDU的没有考虑入度不能大于一. 题意:用树的定义来 判断吧,无环,n个结点最多有n-1条边,不然就会有环.只有一个入度为0的结点,不存在入度大于1的结点. 思路:并查集. AC代码: #include<stdio.h> #include<string.h> #define N 100005 int in[N],pre[N],a,b,c[N]; void init()//初始化 { for(i…

HDU认为1>2,3>2不是树,POJ认为是,而Virtual Judge上引用的是POJ数据这就是唯一的区别....(因为这个瞎折腾了半天) 此题因为是为了熟悉并查集而刷,其实想了下其实好好利用sort应该能更简单A掉,下次有空再去试试... 题目大意:判断是否为树,so: 1,无环: 2,除了根,所有的入度为1,根入度为0: 3,这个结构只有一个根,不然是森林了:4.空树也是树,即第一次输入的两个数字为0 0则是树,其他时候输入只是结束条件 因为POJ和HDU题面一样,要求不一样,所以这题…

Description A tree is a well-known data structure that is either empty (null, void, nothing) or is a set of one or more nodes connected by directed edges between nodes satisfying the following properties. There is exactly one node, called the root, t…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 23312    Accepted Submission(s): 5338 Problem Description A tree is a well-known data structure that is either empty (null, void, no…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 16702    Accepted Submission(s): 3761 Problem Description A tree is a well-known data structure that is either empty (null, void, n…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 20416    Accepted Submission(s): 4628 Problem Description A tree is a well-known data structure that is either empty (null, void, n…

推断是否为树 森林不是树 空树也是树 成环不是树 数据: 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 1 0 0 1 2 2 3 4 5 0 0 2 5 0 0 ans: no no yes #include <stdio.h> #include <string.h> #include <stdlib.h> #include <limits.h> #include <malloc.h> #include <ctype…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 20222    Accepted Submission(s): 456 Problem Description A tree is a well-known data structure that is either empty (null, void, not…

题意:判断有向图是否为树 链接:点我 这题用并查集判断连通,连通后有且仅有1个入度为0,其余入度为1,就是树了 #include<cstdio> #include<iostream> #include<algorithm> #include<cstring> #include<cmath> #include<queue> #include<map> using namespace std; #define MOD 1000…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 19907    Accepted Submission(s): 4472 Problem Description A tree is a well-known data structure that is either empty (null, void, no…

题目大意: 给你两个节点,前者指向后者(可以认为前者是后者的父节点),然后让你判断是否是一棵树. 解题思路: 先说说这道题和小希的迷宫(HDU1272)那道题的区别,前者给出的两个点是有方向的,而后者是没有的,这就是唯一的区别.再者这道题其实就是让你判断所有的点最后所形成的图是否是一棵树.做这道题时错误了很多遍,细想之,主要是开始思路不好,很容易乱,理清思路让代码变得清晰起来就好了.判断一个图是否为一棵树.有三个重要条件(比小希的迷宫多了一个条件): 1:已经在一个集合里面的两个数不能再同时出现…

#include<stdio.h>//判断是否有环,判断是否有点,判断是否是一个父节点 #include<string.h> #define N 1000000 int pre[N+10],dis[N+10]; int find(int n ) { if(pre[n]!=n) return pre[n]=find(pre[n]); return pre[n]; } int main() { int n,m,i,a,b,j,cnt,flag,f1,f2,k=0,min,max; wh…

根据题目所给的3个不符合情况的条件,一个个判断图是否符合这3个条件即可 1.不能出现内部环,拓扑排序判断 2.不能有超过1个点的入度为0,因为只有一个树根 3.每个点最多一个入度 这里要注意的一点是这个点的数字是乱给的,所以最大值为8,但实际上不一定有8个点,这里记录一个最大值的参数,和一个总共点数的参数来进行判断即可 #include <cstdio> #include <cstring> #include <iostream> using namespace std…

Is It A Tree?Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 29483    Accepted Submission(s): 6775 Problem DescriptionA tree is a well-known data structure that is either empty (null, void, noth…

.,. 还是待整理 #include <stdio.h> const; typedef struct { int num,root,conn;//数据.根.入度 }Node; Node node[max_num]; void init() { for; i < max_num; i++) { node;//入度初始化为0 node[i].root= i;//根记录为自身 node;//标记数字是否被使用过,0:没有被使用过,1:使用过了 } } int find_root(int a)…

HDU 1000 A + B Problem  I/O HDU 1001 Sum Problem  数学 HDU 1002 A + B Problem II  高精度加法 HDU 1003 Maxsum  贪心 HDU 1004 Let the Balloon Rise  字典树,map HDU 1005 Number Sequence  求数列循环节 HDU 1007 Quoit Design  最近点对 HDU 1008 Elevator  模拟 HDU 1010 Tempter of th…

参考网址:http://blog.sina.com.cn/s/blog_6827ac4a0100nyjy.html 解题思路: 由于这里出现的数字不一定连续的数字都会出现,所以设一个mark来标记数字是否出现过.每次输入一对数字的关系则进行查找根结点的函数,即: if(aa==bb) { flag=1; } 如果能查找到根结点就证明二者已经是相通的,再输入二者的关系就变成有多条相通的路径了.如果不能查找到根结点则继续标记他们的关系.到一个数据输入结束后,再进行判断,是否输入的关系每个数字之间都有…

来源 hdu 1325 A tree is a well-known data structure that is either empty (null, void, nothing) or is a set of one or more nodes connected by directed edges between nodes satisfying the following properties. There is exactly one node, called the root, t…

Is It A Tree? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 6961    Accepted Submission(s): 1619 [题目链接]http://acm.hdu.edu.cn/showproblem.php?pid=1325 这题如果用并查集做的话,最后判断的时候还是要看一个结点的入度是否为大于1(纯并查集的…

Problem Description As we all know, machine scheduling is a very classical problem in computer science and has been studied for a very long history. Scheduling problems differ widely in the nature of the constraints that must be satisfied and the typ…

Machine Schedule As we all know, machine scheduling is a very classical problem in computer science and has been studied for a very long history. Scheduling problems differ widely in the nature of the constraints that must be satisfied and the type o…

HDU 模拟题, 枚举1002 1004 1013 1015 1017 1020 1022 1029 1031 1033 1034 1035 1036 1037 1039 1042 1047 1048 1049 1050 1057 1062 1063 1064 1070 1073 1075 1082 1083 1084 1088 1106 1107 1113 1117 1119 1128 1129 1144 1148 1157 1161 1170 1172 1177 1197 1200 1201…

转自——http://blog.csdn.net/qwe20060514/article/details/8112550 =============================以下是最小生成树+并查集======================================[HDU]1213   How Many Tables   基础并查集★1272   小希的迷宫   基础并查集★1325&&poj1308  Is It A Tree?   基础并查集★1856   More i…

PS:做到第四题才发现 2,3题的路径压缩等于没写 How Many Tables Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 14542    Accepted Submission(s): 7132 Problem Description Today is Ignatius' birthday. He invites a lot…

传送门: http://acm.hdu.edu.cn/showproblem.php?pid=1116 Play on Words Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 9939    Accepted Submission(s): 3399 Problem Description Some of the secret doo…

King's Game 题目连接: http://acm.hdu.edu.cn/showproblem.php?pid=5643 Description In order to remember history, King plans to play losephus problem in the parade gap.He calls n(1≤n≤5000) soldiers, counterclockwise in a circle, in label 1,2,3...n. The firs…

转载:from http://blog.csdn.net/qq_28236309/article/details/47818349 基础题:1000.1001.1004.1005.1008.1012.1013.1014.1017.1019.1021.1028.1029. 1032.1037.1040.1048.1056.1058.1061.1070.1076.1089.1090.1091.1092.1093. 1094.1095.1096.1097.1098.1106.1108.1157.116…

Can you find it? Time Limit: 10000/3000 MS (Java/Others)    Memory Limit: 32768/10000 K (Java/Others)Total Submission(s): 8506    Accepted Submission(s): 2216 Problem Description Give you three sequences of numbers A, B, C, then we give you a number…

=============================以下是最小生成树+并查集====================================== [HDU] 1213 How Many Tables 基础并查集★ 1272 小希的迷宫 基础并查集★ 1325&&poj1308 Is It A Tree? 基础并查集★ 1856 More is better 基础并查集★ 1102 Constructing Roads 基础最小生成树★ 1232 畅通工程 基础并查集★ 123…