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 ll long long
#define rep(i,l,r)for(ll i=(l);i<(r);i++)

//union-find
#define UFLIMIT (1<<17)
int unicnt[UFLIMIT+10];//正ならcnt、非正なら根のindex
void ufinit(int n){rep(i,0,n)unicnt[i]=1;}
int root(int x){return unicnt[x]<=0?-(unicnt[x]=-root(-unicnt[x])):x;}
int same(int x,int y){return root(x)==root(y);}
void uni(int x,int y){if((x=root(x))==(y=root(y)))return;if(unicnt[x]<unicnt[y]){int t=x;x=y;y=t;}unicnt[x]+=unicnt[y];unicnt[y]=-x;}
#undef UFLIMIT

int main(){
	int n,m;
	scanf("%d%d",&n,&m);
	ufinit(n);
	while(m--){
		int a,b;
		scanf("%d%d",&a,&b);
		uni(a,b);
	}
	scanf("%d",&m);
	while(m--){
		int a,b;
		scanf("%d%d",&a,&b);
		puts(same(a,b)?"yes":"no");
	}
}