Codeforces Round #286 (Div. 2) B 并查集
1 second
256 megabytes
standard input
standard output
Mr. Kitayuta has just bought an undirected graph consisting of n vertices and m edges. The vertices of the graph are numbered from 1 to n. Each edge, namely edge i, has a color ci, connecting vertex ai and bi.
Mr. Kitayuta wants you to process the following q queries.
In the i-th query, he gives you two integers — ui and vi.
Find the number of the colors that satisfy the following condition: the edges of that color connect vertex ui and vertex vi directly or indirectly.
The first line of the input contains space-separated two integers — n and m (2 ≤ n ≤ 100, 1 ≤ m ≤ 100), denoting the number of the vertices and the number of the edges, respectively.
The next m lines contain space-separated three integers — ai, bi (1 ≤ ai < bi ≤ n) and ci (1 ≤ ci ≤ m). Note that there can be multiple edges between two vertices. However, there are no multiple edges of the same color between two vertices, that is, if i ≠ j, (ai, bi, ci) ≠ (aj, bj, cj).
The next line contains a integer — q (1 ≤ q ≤ 100), denoting the number of the queries.
Then follows q lines, containing space-separated two integers — ui and vi (1 ≤ ui, vi ≤ n). It is guaranteed that ui ≠ vi.
For each query, print the answer in a separate line.
4 5
1 2 1
1 2 2
2 3 1
2 3 3
2 4 3
3
1 2
3 4
1 4
2
1
0
5 7
1 5 1
2 5 1
3 5 1
4 5 1
1 2 2
2 3 2
3 4 2
5
1 5
5 1
2 5
1 5
1 4
1
1
1
1
2
Let's consider the first sample.
The figure above shows the first sample.
- Vertex 1 and vertex 2 are connected by color 1 and 2.
- Vertex 3 and vertex 4 are connected by color 3.
- Vertex 1 and vertex 4 are not connected by any single color.
题意:n个点的图 m条边 两个点间可以有多条边 但是两点间相同颜色的边只能有一条 q个查询 判断 u-v间可以通过多少种颜色的边联通
题解:并查集处理
#pragma comment(linker, "/STACK:102400000,102400000")
#include <cstdio>
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <cctype>
#include <map>
#include <set>
#include <queue>
#include <bitset>
#include <string>
#include <complex>
#define ll __int64
#define mod 1000000007
using namespace std;
int n,m;
int fa[][];
int find(int root,int c)
{
if(fa[c][root]==root)
return root;
else
return fa[c][root]=find(fa[c][root],c);
}
void unio(int a,int b,int c)
{
int aa=find(a,c);
int bb=find(b,c);
if(aa!=bb)
fa[c][aa]=bb;
}
int main()
{
scanf("%d %d",&n,&m);
for(int i=;i<=m;i++)
for(int j=;j<=n;j++)
fa[i][j]=j;
int a,b,c;
for(int i=;i<=m;i++)
{
scanf("%d %d %d",&a,&b,&c);
unio(a,b,c);
}
int q;
scanf("%d",&q);
for(int i=;i<=q;i++)
{
scanf("%d %d",&a,&b);
int ans=;
for(int j=;j<=m;j++)
{
if(find(a,j)==find(b,j))
ans++;
}
printf("%d\n",ans);
}
return ;
}
Codeforces Round #286 (Div. 2) B 并查集的更多相关文章
- Codeforces Round #376 (Div. 2) C. Socks---并查集+贪心
题目链接:http://codeforces.com/problemset/problem/731/C 题意:有n只袜子,每只都有一个颜色,现在他的妈妈要去出差m天,然后让他每天穿第 L 和第 R 只 ...
- Codeforces Round #541 (Div. 2) D 并查集 + 拓扑排序
https://codeforces.com/contest/1131/problem/D 题意 给你一个n*m二维偏序表,代表x[i]和y[j]的大小关系,根据表构造大小分别为n,m的x[],y[] ...
- DFS/并查集 Codeforces Round #286 (Div. 2) B - Mr. Kitayuta's Colorful Graph
题目传送门 /* 题意:两点之间有不同颜色的线连通,问两点间单一颜色连通的路径有几条 DFS:暴力每个颜色,以u走到v为结束标志,累加条数 注意:无向图 */ #include <cstdio& ...
- 水题 Codeforces Round #286 (Div. 2) A Mr. Kitayuta's Gift
题目传送门 /* 水题:vector容器实现插入操作,暴力进行判断是否为回文串 */ #include <cstdio> #include <iostream> #includ ...
- Codeforces Round #286 (Div. 1) D. Mr. Kitayuta's Colorful Graph 并查集
D. Mr. Kitayuta's Colorful Graph Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/ ...
- CodeForces Round #286 Div.2
A. Mr. Kitayuta's Gift (枚举) 题意: 给一个长度不超过10的串,问能否通过插入一个字符使得新串成为回文串. 分析: 因为所给的串很多,所以可以枚举 “在哪插入” 和 “插入什 ...
- Codeforces Round #286 (Div. 1) 解题报告
A.Mr. Kitayuta, the Treasure Hunter 很显然的一个DP,30000的数据导致使用map+set会超时.题解给了一个非常实用的做法,由于每个点有不超过250种状态,并且 ...
- Codeforces Round #286 (Div. 1) B. Mr. Kitayuta's Technology (强连通分量)
题目地址:http://codeforces.com/contest/506/problem/B 先用强连通判环.然后转化成无向图,找无向图连通块.若一个有n个点的块内有强连通环,那么须要n条边.即正 ...
- Codeforces Round #286 Div.1 A Mr. Kitayuta, the Treasure Hunter --DP
题意:0~30000有30001个地方,每个地方有一个或多个金币,第一步走到了d,步长为d,以后走的步长可以是上次步长+1,-1或不变,走到某个地方可以收集那个地方的财富,现在问走出去(>300 ...
随机推荐
- vue 跳转到外部 后回跳
微信 vue 跳转到外部 后回跳 ,比如登陆 授权操作 .需要 路由 先跳转到一个中间页面 后再跳转到授权服务器!而不能跳转前的页面与回跳后的页面相同 不然回跳可能会出现空白 路由不解析.
- 吴恩达 Deep learning 第一周 深度学习概论
知识点 1. Relu(Rectified Liner Uints 整流线性单元)激活函数:max(0,z) 神经网络中常用ReLU激活函数,与机器学习课程里面提到的sigmoid激活函数相比有以下优 ...
- Sublime Text 2 - Unable to find git.exe 错误
今日打开 Sublime Text 2,随即弹出 Package Control - Unable to find git.exe 错误.如下, 原因:曾经通过 git clone 命令获取过 Sub ...
- Linux下的计算器(bc、expr、dc、echo、awk)知多少?
linux 其他知识目录 原文链接:http://blog.chinaunix.net/uid-24673811-id-1760837.html linux下的三个命令可以用来作计算,下面一一讲解用法 ...
- 清空git缓存
git rm -r --cached .git add . git commit -m 'update .gitignore' 读了下git文档,才发现,这些东西其实很简单,很容易理解.cached其 ...
- C++ 名字空间namespace的使用
A namespace is a scope.C++ provides namespaces to prevent name conflicts.A namespace is a mechanism ...
- Scrum立会报告+燃尽图(十月十七日总第八次)
本次作业要求参见:https://edu.cnblogs.com/campus/nenu/2018fall/homework/2246 一.小组介绍 组名:杨老师粉丝群 组长:乔静玉 组员:吴奕瑶.公 ...
- 效能检测 psp
1.本周psp: 2.本周进度条: 3.累计进度图(折线图) 4.psp饼状图:
- P4语法(3)Table,Action
Table table是p4的匹配——动作表,定义了匹配字段(key).动作(action)和一些其他相关属性. 其处理数据包的流程: Key construction.建立其匹配字段 Key loo ...
- String、StringBuilder与StringBuffer的区别
1.String类是public.final修饰的. 在Java中,被final修饰的类是不允许被继承的,并且String它的成员方法都默认为final方法. 查看源码得知,String类其实是通过c ...