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 MAX 100000
 
int list[MAX] = {0};
 
void init(){
    int i;
    for(i = 0; i < MAX; i++){
        list[i] = i;
    }
}
 
int find(int n){
    if (n == list[n]) return n;
    return list[n] = find(list[n]);
}
 
int unit_friend(int a,int b){
    if (find(a) == find(b)) return 1;
    else return 0;
}
 
void unit(int a,int b){
    a = find(a);
    b = find(b);
     
    if (a == b)return;
     
    list[b]=a;
}
 
int main(void){
    int num, friend, i, s, t, q;
    init();
    scanf("%d%d", &num, &friend);
    for(i = 0; i < friend; i++){
        scanf("%d%d", &s, &t);
        unit(s,t);
    }
    scanf("%d", &q);
    for(i = 0; i < q; i++){
        scanf("%d%d", &s, &t);
        if (unit_friend(s,t) == 1) printf("yes\n");
        else printf("no\n");
    }
    return 0;
}