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>
int N, m, q;
int vector[100000][100];
int count[100000];
int group[100000];
int ID = 1;
  
void dfs(int s){
    int i;
    group[s]=ID;
    for(i = 0; i < count[s]; i++ ) {
        if ( group[vector[s][i]] == 0 ) dfs(vector[s][i]);
    }
}
  
int main() {
    int i, j, a, b; 
    scanf("%d%d", &N, &m);
    for ( i = 0; i < m; i++ ) {
        scanf("%d%d", &a, &b);
        vector[a][count[a]++] = b;
        vector[b][count[b]++] = a;
    }
    for ( i = 0; i < N; i++ ) {
        if ( group[i] == 0 ) {
            dfs(i);
            ID++;
        }
    } 
    scanf("%d",&q);
    for ( i = 0; i < q; i++ ) {
        scanf("%d%d", &a, &b);
        if ( group[a] == group[b] ) printf("yes\n");
        else printf("no\n");
    }
  
    return 0;
}