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: Wrong Answer)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Deque;
import java.util.List;

class Main {

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


		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String[] n_m = br.readLine().split(" ");

		int n = Integer.parseInt(n_m[0]);

		int m = Integer.parseInt(n_m[1]);

		node[] v = new node[n];

		for (int i = 0; i < v.length; i++) {
			v[i] = new node();
		}

		for (int i = 0; i < m; i++) {

			String[] node_to = br.readLine().split(" ");

			int node = Integer.parseInt(node_to[0]);
			int to = Integer.parseInt(node_to[1]);

			v[node].graph.add(to);
			v[to].graph.add(node);

		}

		int q = Integer.parseInt(br.readLine());

		StringBuilder sb = new StringBuilder();

		for (int i = 0; i < q; i++) {

			String[] nodenumbers = br.readLine().split(" ");

			int nownode = Integer.parseInt(nodenumbers[0]);

			int targetnode = Integer.parseInt(nodenumbers[1]);

			if (dfs(v, nownode, targetnode, n)) {
				sb.append("yes");
			} else {
				sb.append("no");
			}
			sb.append("\n");
		}

		System.out.print(sb);


	}
	static boolean visied[] = new boolean[10000];
	static Deque<Integer> dfs = new ArrayDeque<Integer>();

	static boolean dfs(node[] v, int startnode, int targetnode, int nodes) {

		boolean judge = false;


		dfs.push(startnode);


		while (!(dfs.isEmpty())) {

			int now_node = dfs.pop();

			visied[now_node] = true;

			for (int i = 0; i < v[now_node].graph.size(); i++) {
				int next_node = v[now_node].graph.get(i);
				if (targetnode == next_node) {
					judge = true;
					break;
				}
				if (!(visied[next_node])) {
					dfs.push(next_node);
				}
			}
			if (judge)
				break;
		}

		if (judge) {
			return true;
		} else {
			return false;
		}

	}

	public static class node {

		List<Integer> graph;

		public node() {
			this.graph = new ArrayList<Integer>();
		}
	}

}