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)

#include <stdio.h>
#define Num 100000

int A[Num];

void assign() {
    int i;
    for(i = 0 ; i < Num ; i++)
        A[i] = i;
}

int dsf(int n) {
    /*被リンクの親は常に自分を返し続ける*/
    if(A[n] == n)
        return n;
    /*リンクしているならそのリンクを崩さないように*/
    else
        return A[n] = dsf(A[n]);
}

void LINK(int s , int t) {
    s = dsf(s);
    t = dsf(t);
    
    /*リンクして入れば被リンクの親の名がつく*/
    A[t] = s;
}

int main(void)
{
    int n , m , q;
    int s , t , u , v;
    int i;
    
    assign();
    
    scanf("%d %d" , &n , &m);
    
    for(i = 0 ; i < m ; i++) {
        scanf("%d %d" , &s , &t);
        
        LINK(s , t);
    }
    
    scanf("%d" , &q);
    
    for(i = 0 ; i < q ; i++) {
        scanf("%d %d" , &u , & v);
        
        if(dsf(u) == dsf(v))
            puts("yes");
        else
            puts("no");
    }

    return 0;
}