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: Memory Limit Exceeded)

#include <stdio.h>
#include <stdlib.h>

void search(int **a, int n, char **group, int g_num, int u, int *affiliation) {
  if(group[g_num][u] != 0) return;
  group[g_num][u] = 1;
  affiliation[u] = g_num;
  int i;
  for (i = 0; i < n; i++) {
    if(a[u][i] == 1) {
      search(a,n,group,g_num,i,affiliation);
    }
  }
}

int main()
{
  int i,j,n,m,**a,u,v;
  scanf("%d %d",&n,&m);
  a = (int**)malloc(sizeof(int*) * n);
  for (i = 0; i < n; i++) {
    a[i] = (int*)malloc(sizeof(int) * n);
    for(j = 0; j < n; j++) a[i][j] = 0;
  }
  for (i = 0; i < m; i++) {
    scanf("%d",&u);
    scanf("%d",&v);
    a[u][v] = 1;
    a[v][u] = 1;
 
  }

  char **group;
  group = (char**)malloc(sizeof(char*) * n);
  for (i = 0; i < n; i++) {
    group[i] = (char*)malloc(sizeof(char) * n);
    for(j = 0; j < n; j++) group[i][j] = 0;
  }
  int *affiliation;
  affiliation = (int*)malloc(sizeof(int) * n);
  for (i = 0; i < n; i++) {
    affiliation[i] = -1;
  }

  j = 0;
  for (i = 0; i < n; i++) {
    if(affiliation[i] == -1) {
      search(a,n,group,j,i,affiliation);
      j++;
    }
  }

  int q,s,t;
  scanf("%d",&q);
  for (i = 0; i < q; i++) {
    scanf("%d %d",&s,&t);
    if(group[affiliation[s]][t] == 1) printf("yes\n");
    else printf("no\n");

  }



  for (i = 0; i < n; i++) {
    free(a[i]);
    free(group[i]);
  }
  free(a);
  free(group);
  free(affiliation);
  return 0;
}