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 C# (judge verdict: Time Limit Exceeded)

using System;
using System.Collections.Generic;
using System.Text;
					
public class Program
{	
	public static void Main()
	{
		int[] tmp = Array.ConvertAll(Console.ReadLine().Split(" ".ToCharArray()), int.Parse);
		int n = tmp[0];
		int m = tmp[1];
		
		Node[] nodes = new Node[n];
		for(int i = 0; i < n; i++) {
			nodes[i] = new Node(i);
		}
		
		for(int i = 0; i < m; i++) {
			tmp = Array.ConvertAll(Console.ReadLine().Split(" ".ToCharArray()), int.Parse);
			int s = tmp[0];
			int t = tmp [1];
			
			nodes[s].Children.Add(nodes[t]);
			nodes[t].Children.Add(nodes[s]);
		}
		
		int q = int.Parse(Console.ReadLine());
		StringBuilder sb = new StringBuilder();
		for(int i = 0; i < q; i++) {
			Initialize(nodes);
			
			tmp = Array.ConvertAll(Console.ReadLine().Split(" ".ToCharArray()), int.Parse);
			int s = tmp[0];
			int t = tmp [1];
			BFS(nodes[s], nodes[t], nodes[s].Children.ToArray());
			sb.AppendLine( (nodes[t].d != -1)? "yes" : "no" );
		}
		Console.Write(sb);
	}
	
	static void Initialize(Node[] nodes)
	{
		foreach(var node in nodes) {
			node.d = 0;
			node.Added = false;
		}
	}
	
	static void BFS(Node start, Node goal,Node[] onWays)
	{
		if(start == goal) return;
		else {
			goal.d++;
 
			List<Node> nexts = new List<Node>();
			foreach (var o in onWays) {
				if(o == goal) return;
 
				if(!o.Added) {
					foreach(Node p in o.Children.ToArray()){
						if(p != start) nexts.Add(p);
					}
					o.Added = true;
				}
			}
			if(nexts.Count != 0) BFS(start, goal, nexts.ToArray());
			else goal.d = -1;
		}
	}
	
}

class Node
{
	public bool Added;
	public int d;
	public int Id { get; private set; }
	public List<Node> Children = new List<Node>();
	
	public Node (int id)
	{
		this.Id = id;
	}
	
	public override string ToString()
	{
		return (Id + 1) + " " + d;
	}
}