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: Runtime Error)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {

	private class DisjointSet {
		
		int[] p;
		int[] rank;

		public DisjointSet(int size) {
			p = new int[size];
			rank = new int[size];
			for (int i = 0; i < size; i++) makeSet(i);
		}

		private void makeSet(int x) {
			p[x] = x;
			rank[x] = 0;
		}
		
		public boolean same(int x, int y) {
			return findSet(x) == findSet(y);
		}

		private int findSet(int x) {
			if (p[x] != x) {
				p[x] = findSet(p[x]);
			}
			return p[x];
		}
		
		public void unite(int x, int y) {
			link(findSet(x), findSet(y));
		}

		private void link(int x, int y) {
			if (rank[x] < rank[y]) {
				p[y] = x;
			} else {
				p[x] = y;
				if (rank[x] == rank[y]) {
					rank[y]++;
				}
			}
		}
	}	
	
	public static void main(String[] args) throws IOException {
		new Main().run();
	}
	
	private void run() throws IOException {
		BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(reader.readLine());
		int n = Integer.parseInt(st.nextToken());
		DisjointSet ds = new DisjointSet(n);
		int m = Integer.parseInt(st.nextToken());
		for (int i = 0; i < m; i++) {
			st = new StringTokenizer(reader.readLine());
			int id1 = Integer.parseInt(st.nextToken());
			int id2 = Integer.parseInt(st.nextToken());
			ds.unite(id1, id2);
		}
		
		int q = Integer.parseInt(reader.readLine());
		for (int i = 0; i < q; i++) {
			st = new StringTokenizer(reader.readLine());
			int id1 = Integer.parseInt(st.nextToken());
			int id2 = Integer.parseInt(st.nextToken());
			if (ds.same(id1, id2)) {
				System.out.println("yes");
			} else {
				System.out.println("no");
			}
		}
		reader.close();
	}
}