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: Runtime Error)

#include<stdio.h>

#define MAX 1000
#define white 0
#define gray 1
#define black 2

int n,m,g[MAX][MAX] = {0};
int s,t,flag,color[MAX];

void visit(int);

int main(){
  int i,j,q;

  scanf("%d %d",&n,&m);
  for(i=0;i<m;i++){
    scanf("%d %d",&s,&t);
    g[s][t] = g[t][s] = 1;
  }

  scanf("%d",&q);
  for(i=0;i<q;i++){
    scanf("%d %d",&s,&t);
    for(j=0;j<n;j++)color[j] = white;
    flag = 0;
    visit(s);
    if(flag == 1)printf("yes\n");
    else printf("no\n");
  }

  return 0;
}

void visit(int u){
  int v;

  if(flag == 1)return;
  color[u] = gray;

  for(v=0;v<n;v++){
    if(g[u][v] == 0)continue;
    if(color[v] == white)visit(v);
  }

  if(g[u][t] == 1 || g[t][u] == 1)flag =  1;
}