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: Wrong Answer)

using System;
using System.IO;
using System.Linq;

namespace Graph_I
{
    class Connected_Components
    {
        static int[] connectTree;
        static int[] height;

        public static int Root(int x)
        {
            if (connectTree[x] == x) return x;
            else return connectTree[x] = Root(connectTree[x]);
        }

        public static void Connect(int x, int y)
        {
            if (IsConnected(x, y)) return;

            if (height[x] < height[y])
                connectTree[x] = y;
            else
            {
                connectTree[y] = x;
                if (height[x] == height[y]) height[x]++;
            }
        }

        public static bool IsConnected(int x, int y) { return Root(x) == Root(y); }

        static void Main(string[] args)
        {
            var nm = Console.ReadLine().Split(' ').Select(s => int.Parse(s)).ToArray();
            var n = nm[0];
            var m = nm[1];

            connectTree = new int[n];
            height = new int[n];
            for (int i = 0; i < connectTree.Length; i++) connectTree[i] = i;

            for (int i = 0; i < m; i++)
            {
                var st = Console.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray();
                var s = st[0];
                var t = st[1];
                Connect(s, t);
            }

            var q = int.Parse(Console.ReadLine());

            var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
            Console.SetOut(sw);
            for (int i = 0; i < q; i++)
            {
                var st = Console.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray();
                Console.WriteLine(IsConnected(st[0], st[1]) ? "yes" : "no");
            }
        }
    }
}