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.util.LinkedList;

public class Main {

	public static void main(String[] args) throws Exception {
		// TODO ?????????????????????????????????????????????
		int n = ReadIntMan.readint();
		int m = ReadIntMan.readint();

		Node[] v = new Node[n];
		for (int i=0; i < n; i++) {
			v[i] = new Node();
		}

		for (int i=0; i < m; i++) {
			int s = ReadIntMan.readint();
			int t = ReadIntMan.readint();

			v[s].friends.add(t);
			v[t].friends.add(s);
		}

		for (int id=0; id < n; id++) {
			decompose(v, id, id);
		}

		StringBuilder ans = new StringBuilder();

		int q = ReadIntMan.readint();
		for (int i=0; i < q; i++) {
			int s = ReadIntMan.readint();
			int t = ReadIntMan.readint();

			if (v[s].label == v[t].label) ans.append("yes\n");
			else ans.append("no\n");
		}

		System.out.print(ans);
	}

	public static void decompose(Node[] u,int id, int label) {
		if (u[id].label != -1) return;
		u[id].label = label;

		for (int i=0; i < u[id].friends.size(); i++) {
			int f = u[id].friends.get(i);
			decompose(u, f, label);
		}
	}

	public static class Node {
		int label;

		LinkedList<Integer> friends;

		public Node() {
			this.label = -1;
			this.friends = new LinkedList<>();
		}
	}

	public static class ReadIntMan {
		public static int readint() throws Exception {
			int c = System.in.read();

			while (spaceorenter(c)) {
				c = System.in.read();
			}

			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = System.in.read();
			}

			int n = 0;
			while (! spaceorenter(c)) {
				n = 10*n;
				n = n + c - '0';
				c = System.in.read();
			}

			return sgn * n;
		}

		private static boolean spaceorenter(int c) {
			return c == ' ' || c == '\n' || c == '\r';
		}
	}
}