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>
#include <stdlib.h>


typedef struct link_t{
	int id;
	struct link_t *next;
}LINK_T;


typedef struct{
	int color;
	struct link_t *next;
}USER_T;


void Bfs(USER_T *user, int id, int color)
{
	LINK_T *p;


	if(user[id].color != -1)
		return;

	user[id].color = color;

	for(p = user[id].next; p != NULL; p = p->next)
		Bfs(user, p->id, color);
}

LINK_T *my_alloc()
{
	LINK_T *p;

	if( (p = (LINK_T *)malloc(sizeof(LINK_T))) == NULL){
		printf("malloc error\n");
		exit(1);
	}

	return p;
}

int main()
{
	int users, relation_n;
	int q_n;
	USER_T *user;
	LINK_T *p;
	int id, sub_id, r_id;	// relation_id
	int i, j;


	scanf("%d %d", &users, &relation_n);

	user = (USER_T *)malloc(sizeof(USER_T) * users);

	for(i = 0; i < users; i++){
		user[i].color = -1;
		user[i].next = NULL;
	}

	for(i = 0; i < relation_n; i++){
		scanf("%d %d", &id, &r_id);
		p = my_alloc();
		p->id = r_id;
		p->next = user[id].next;
		user[id].next = p;

		p = my_alloc();
		p->id = id;
		p->next = user[r_id].next;
		user[r_id].next = p;
	}
/*
	for(i = 0; i < users; i++){
		printf("<%d>\n", i);
		for(p = user[i].next; p != NULL; p = p->next){
			printf(" %d", p->id);
		}
		printf("\n");
	}
*/
	// BFS(グループ分け)
	for(i = 0; i < users; i++)
		Bfs(user, i, i + 1);

	scanf("%d", &q_n);
	for(i = 0; i < q_n; i++){
		scanf("%d %d", &id, &sub_id);
		if(user[id].color == user[sub_id].color)
			printf("yes\n");
		else
			printf("no\n");
	}


	return 0;
}