Problem:
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Connected Components

Write a program which reads relations in a SNS (Social Network Service), and judges that given pairs of users are reachable each other through the network.

Input

In the first line, two integer $n$ and $m$ are given. $n$ is the number of users in the SNS and $m$ is the number of relations in the SNS. The users in the SNS are identified by IDs $0, 1, ..., n-1$.

In the following $m$ lines, the relations are given. Each relation is given by two integers $s$ and $t$ that represents $s$ and $t$ are friends (and reachable each other).

In the next line, the number of queries $q$ is given. In the following $q$ lines, $q$ queries are given respectively. Each query consists of two integers $s$ and $t$ separated by a space character.

Output

For each query, print "yes" if $t$ is reachable from $s$ through the social network, "no" otherwise.

Constraints

$2 \leq n \leq 100,000$

$0 \leq m \leq 100,000$

$1 \leq q \leq 10,000$

Sample Input

10 9
0 1
0 2
3 4
5 7
5 6
6 7
6 8
7 8
8 9
3
0 1
5 9
1 3

Sample Output

yes
yes
no

Solution in C++ (judge verdict: Accepted)

#include<iostream>
#include<algorithm>
#include<vector>
#include<stack>
using namespace std;
static const int MAX = 100000;
int n;
int color[MAX];
vector<int> v[MAX];
void b(int s, int t){
	stack<int> S;
	S.push(s);
	int tp;
	color[s] = t;
	while (!S.empty()){
		int tp = S.top(); S.pop();
		for (int i = 0; i < v[tp].size(); i++){
			if (color[v[tp][i]] == MAX){
				color[v[tp][i]] = t;
				S.push(v[tp][i]);
			}
		}
	}
}
void a(){
	for (int i = 0; i < n; i++){
		color[i] = MAX;
	}
	int id = 0;
	for (int i = 0; i < n; i++){
		id++;
		if(color[i] == MAX)b(i,id);
	}
}
int main(){
	int m, s, t;
	int q;
	cin >> n >> m;
	for (int i = 0; i < m; i++){
		cin >> s >> t;
		v[s].push_back(t);
		v[t].push_back(s);
	}
	a();
	cin >> q;
	for (int i = 0; i < q; i++){
		cin >> s >> t;
		if (color[s] == color[t]) cout << "yes" << endl;
		else cout << "no" << endl;
 	}
	return 0;
}