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.io.IOException;
import java.util.Scanner;

public class Main {
	static int time = 0;

	public static void main(String[] args) throws IOException {

		Scanner scan = new Scanner(System.in);
		// Scanner scan = new Scanner(new
		// File("D:\\UserArea\\J0124567\\Downloads\\ALDS1_6_A-in9.txt"));

		int n = scan.nextInt();
		Sns sns = new Sns(n);

		int m = scan.nextInt();
		for (int i = 0; i < m; i++)
			sns.addRel(scan.nextInt(), scan.nextInt());

		int q = scan.nextInt();
		for (int i = 0; i < q; i++)
			if (sns.isFriends(scan.nextInt(), scan.nextInt()))
				System.out.println("yes");
			else
				System.out.println("no");

		scan.close();
		System.exit(0);
	}
}

class Sns {

	int[] leader;
	int[] member;

	public Sns(int n) {
		leader = new int[n];
		member = new int[n];
		for (int i = 0; i < n; i++) {
			leader[i] = i;
			member[i] = 1;
		}
	}

	public boolean isFriends(int s, int t) {
		if (top(s) == top(t))
			return true;
		else
			return false;
	}

	private int top(int s) {
		if (leader[s] == s)
			return s;
		else
			return top(leader[s]);
	}

	public void addRel(int s, int t) {
		if (isFriends(s, t))
			return;
		int tt = top(t);
		int st = top(s);
		if (member[st] < member[tt]) {
			leader[st] = tt;
			member[tt] += member[st];
		} else {
			leader[tt] = st;
			member[st] += member[tt];
		}
	}

}