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.collection.mutable.ArrayBuffer
import scala.io.StdIn

object Main extends App {

  val Array(n, m) = StdIn.readLine().split(' ').map(_.toInt)
  val groupIndex = Array.fill[Int](n)(-1)
  val friends = Array.fill[ArrayBuffer[Int]](n)(ArrayBuffer.empty[Int])
  
  (0 until m).foreach { _ =>
    val a = StdIn.readLine().split(' ').map(_.toInt)
    friends(a(0)) += a(1)
    friends(a(1)) += a(0)
  }

  def depthFirstSearch(u: Int, grpId: Int): Unit = {
    groupIndex(u) = if(groupIndex(u) == -1) grpId else groupIndex(u)
    friends(u).foreach { v =>
      if(groupIndex(v) == -1){
        depthFirstSearch(v, grpId)
      }
    }
  }


  var idx = 1
  (0 until n).foreach { v =>
    if(groupIndex(v) == -1){
      depthFirstSearch(v, idx + 1)
      idx += 1
    }
  }

  val q = StdIn.readLine().toInt
  //val sbbuff = new StringBuilder
  //println(s"q: $q")
  (0 until q).foreach { _ =>
    val ql = StdIn.readLine().split(' ').map(_.toInt)
    if(groupIndex(ql(0)) == groupIndex(ql(1))) {
      println("yes")
    } else {
      println("no")
    }
  }

  //print(sbbuff.toString())
  
}