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 Rust (judge verdict: Accepted)

use std::collections::VecDeque;
use std::io::*;
use std::str::FromStr;

fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin
        .bytes()
        .map(|c| c.expect("failed to read char") as char)
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("failed to parse token")
}

fn dfs(color: &mut Vec<Option<usize>>, target: usize, id: usize, g: &mut Vec<Vec<usize>>) {
    let mut s: VecDeque<usize> = VecDeque::new();
    s.push_back(target);
    color[target] = Some(id);

    while s.len() > 0 {
        let u: usize = s.pop_front().unwrap() as usize;
        for i in 0..g[u].len() {
            let v: usize = g[u][i];
            if color[v] == None {
                dfs(color, v, id, g);
            }
        }
    }
}

fn assign_color(color: &mut Vec<Option<usize>>, g: &mut Vec<Vec<usize>>, n: usize) {
    let mut id: usize = 1;
    for u in 0..n {
        if color[u] == None {
            id = id + 1;
            dfs(color, u, id, g);
        }
    }
}

fn main() {
    let n: usize = read();
    let m: usize = read();
    let mut g: Vec<Vec<usize>> = vec![vec![]; n];
    let mut color: Vec<Option<usize>> = vec![None; n];
    for _ in 0..m {
        let person_index1: usize = read();
        let person_index2: usize = read();
        g[person_index1].push(person_index2);
        g[person_index2].push(person_index1);
    }
    assign_color(&mut color, &mut g, n);
    let question_count: usize = read();
    for _ in 0..question_count {
        let from: usize = read();
        let to: usize = read();
        if color[from] == color[to] {
            println!("yes");
        } else {
            println!("no");
        }
    }
}