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 JAVA (judge verdict: Accepted)

import java.util.*;

public class Main {
	public static void main(String[]  args) {
		Scanner scanner = new Scanner(System.in);

		int n = scanner.nextInt();
		int m = scanner.nextInt();
		
		List<List<Integer>> v = new ArrayList<>(n);
		int g_[] = new int[n];
		for (int i = 0; i < n; i ++) {
			v.add(new LinkedList<Integer>());
			g_[i] = -1;
		}
		
		for (int i = 0; i < m; i ++) {
			int s = scanner.nextInt();
			int t = scanner.nextInt();
			
			v.get(s).add(t);
			v.get(t).add(s);
		}
		
		Queue<Integer> queue = new ArrayDeque<>(n);
		
		for (int i = 0; i < n; i ++) {
			if(g_[i] != -1) continue;
			g_[i] = i;
			
			queue.add(i);
			while(!queue.isEmpty()) {
				int u = queue.remove();
				
				for (int j: v.get(u)) {
					if (g_[j] == -1) {
						g_[j] = i;
						queue.add(j);
					}
				}
			}
		}
		
		int q = scanner.nextInt();
		
		for (int i = 0; i < q; i ++) {
			if (g_[scanner.nextInt()] == g_[scanner.nextInt()]) {
				System.out.println("yes");
			} else {
				System.out.println("no");
			}
		}
		
		scanner.close();
	}
}