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)

//2020.1.26
//s1270188 xxxmk2
//alds1_11d

#include<stdio.h>
#include<stdlib.h>
#define N 100001

//struct
struct node{
  int id;
  struct node* next;
};

//global
struct node data[N];
int num, color[N];

//prototype
void insert(int,int);
void dfs(int,int);

int main(){
  int i, j, a, b;
  //input
  scanf("%d",&num);
  for(i=0;i<num;i++)  data[i].next=NULL;

  scanf("%d",&j);
  for(i=0;i<j;i++) {
    scanf("%d %d",&a,&b);
    insert(a,b);
    insert(b,a);
  }

  /*
  struct node *n;
  for(i=0;i<=num;i++){
    printf("%2d:",i);
    for(n=data[i].next;n!=NULL;n=n->next) printf(" %d",n->id);
    printf("\n");
  }
  */

  //dfs
  for(i=0;i<num;i++) color[i]=-1;
  j=1;
  for(i=0;i<num;i++)
    if(color[i]==-1) dfs(i,j++);
  
  //question
  scanf("%d",&j);
  for(i=0;i<j;i++){
    scanf("%d %d",&a,&b);
    if(color[a]==color[b]) printf("yes\n");
    else printf("no\n");
  }
  
  return 0;
}


void insert(int a, int b){
  struct node *n, *tmp;

  n=malloc(sizeof(struct node));
  n->id=b;
  n->next=NULL;

  for(tmp=&data[a];tmp->next!=NULL;tmp=tmp->next);
  tmp->next=n;
}


void dfs(int u, int c){
  struct node *n;
  
  color[u]=c;
  for(n=data[u].next;n!=NULL;n=n->next){
    if(color[n->id]==-1) dfs(n->id,c);
  }
}