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: Accepted)

using System;
using System.IO;
using System.Linq;
using System.Collections.Generic;

public class Program
{

	public void Proc()
	{
        int[] inpt = Reader.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray();
        int userCount = inpt[0];
        int connectionCount = inpt[1];
        for (int i = 0; i < connectionCount; i++) {
            inpt = Reader.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray();
            inpt.ToList().ForEach(a =>
            {
                if (!Conn.ContainsKey(a))
                {
                    Conn.Add(a, new List<int>());
                }
            });
            this.Conn[inpt[0]].Add(inpt[1]);
            this.Conn[inpt[1]].Add(inpt[0]);
        }
        this.Group = new int[userCount];
        SetDic();
        int queryCount = int.Parse(Reader.ReadLine());
        System.Text.StringBuilder ans = new System.Text.StringBuilder();
        for (int i = 0; i < queryCount; i++) {
            inpt = Reader.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray();
            if(this.Group[inpt[0]] == this.Group[inpt[1]]) {
                ans.AppendLine("yes");
            } else {
                ans.AppendLine("no");
            }
        }
        Console.Write(ans.ToString());
    }

    private void SetDic() {
        int grpNum = 1;
        for (int i = 0; i < this.Group.Length; i++) {
            if(this.Group[i] == 0) {
                this.SetDicSub(i, grpNum);
                grpNum++;
            }
        }
    }
    private void SetDicSub(int userId, int groupId) {
        Stack<int> stk = new Stack<int>();
        this.Group[userId] = groupId;
        stk.Push(userId);
        while(stk.Count>0) {
            int current = stk.Pop();
            if(!Conn.ContainsKey(current)) {
                continue;
            }
            foreach(int next in Conn[current]) {
                if(this.Group[next] == 0) {
                    this.Group[next] = groupId;
                    stk.Push(next);
                }
            }
        }
    }

    private int[] Group;

    private Dictionary<int, List<int>> Conn = new Dictionary<int, List<int>>();


	public class Reader
	{
		private static StringReader sr;
		public static bool IsDebug = false;
		public static string ReadLine()
		{
			if (IsDebug)
			{
				if (sr == null)
				{
					sr = new StringReader(InputText.Trim());
				}
				return sr.ReadLine();
			}
			else
			{
				return Console.ReadLine();
			}
		}
		private static string InputText = @"



10 5
0 1
1 2
2 9
3 4
6 7
12
0 1
0 2
0 9
3 4
6 7
7 6
0 5
0 6
3 7
3 5
5 8
8 5


";
	}

	public static void Main(string[] args)
	{
#if DEBUG
		Reader.IsDebug = true;
#endif
		Program prg = new Program();
		prg.Proc();
	}
}