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 Scala (judge verdict: Accepted)

import scala.io.StdIn.{readInt, readLine};
import scala.collection.immutable.Queue;

object Main {
    def main(args: Array[String]): Unit = {
        val info = readLine.split(" ").map(_.toInt);
        val graph: Array[List[Int]] = new Array[List[Int]](info(0)).map(a => Nil);
        for (i <- (0 until info(1))) {
            val c = readLine.split(" ").map(_.toInt);
            graph(c(0)) = c(1) :: graph(c(0));
            graph(c(1)) = c(0) :: graph(c(1));
        }
        val connList: Array[Int] = buildConnectionList(graph);
        for (i <- (0 until readInt)) {
            val q = readLine.split(" ").map(_.toInt);
            if (connList(q(0)) == connList(q(1))) println("yes") else println("no");
        }
    }
    
    def buildConnectionList(graph: Array[List[Int]]): Array[Int] = {
        val size = graph.length;
        val connList = new Array[Int](size);
        def go(que: Queue[Int], group: Int): Int = {
            que.dequeueOption match {
                case None => group + 1;
                case Some((src, restQue)) => {
                    val newQue = graph(src).filter(dst => connList(dst) == 0).foldLeft(restQue) { (q, dst) => 
                        connList(dst) = group; 
                        q.enqueue(dst);
                    }
                    go(newQue, group);
                }
            }
        }
        (0 until size).foldLeft(1) { (group, i) => 
            if (connList(i) == 0) {connList(i) = group;go(Queue(i), group);} else {group}
        }
        connList;
    }
}