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 CC[MAX];

 void init(){
             int i;
             for(i=0;i<MAX;i++)CC[i]=i;
             }

 int find(int a){
                 if(a==CC[a])return a;
                 return CC[a]=find(CC[a]);
                 }

 int isSame(int a,int b){
                         if(find(a)==find(b))return 1;
                         else return 0;
                         }

 void unite(int a,int b){
                         a=find(a);
                         b=find(b);

                         if(a==b)return;
                         CC[b]=a;
                         }

 int main(){
            int n,m,q,i,j,k;
            init();
            scanf("%d %d",&n,&m);
            for(i=0;i<m;++i){
                             scanf("%d%d",&j,&k);
                             unite(j,k);
                             }
            
            scanf("%d",&q);
            for(i=0;i<q;i++){
                             scanf("%d%d",&j,&k); 
                             if(isSame(j,k))printf("yes\n");
                             else printf("no\n");
                             }
            return 0;
            }