Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)
	m := getNextInt(scanner)
	nodes := make([]Node, n)

	for i := 0; i < n; i++ {
		nodes[i].list = make([]int, 0)
	}

	for i := 0; i < m; i++ {
		s := getNextInt(scanner)
		t := getNextInt(scanner)
		nodes[s].list = append(nodes[s].list, t)
		nodes[t].list = append(nodes[t].list, s)
	}

	c := 1
	for i := 0; i < n; i++ {
		if nodes[i].c == 0 {
			traverse(nodes, i, c)
			c++
		}
	}

	q := getNextInt(scanner)

	for i := 0; i < q; i++ {
		s := getNextInt(scanner)
		t := getNextInt(scanner)
		if nodes[s].c == nodes[t].c {
			fmt.Fprintln(writer, "yes")
			continue
		}
		fmt.Fprintln(writer, "no")
	}

	writer.Flush()
}

// Node ...
type Node struct {
	list []int
	c    int
}

func traverse(nodes []Node, r, c int) {
	nodes[r].c = c
	for _, i := range nodes[r].list {
		if nodes[i].c != 0 {
			continue
		}
		traverse(nodes, i, c)
	}
}

Python: from collections import deque

n, m = map(int, input().split())

G = [[] for i in range(n)]
check, dist = [0 for i in range(n)], [-1 for i in range(n)]


def bfs(s, e):
    for i in range(n):
        check[i], dist[i] = 0, -1
    q = deque()

    check[s], dist[s] = 1, 0
    q.append(s)

    while len(q) != 0:
        u = q.popleft()
        for v in range(len(G[u])):
            if check[G[u][v]] == 0:
                check[G[u][v]], dist[G[u][v]] = 1, dist[u] + 1
                q.append(G[u][v])

        check[u] = 2

    return dist[e]


def main():
    for i in range(m):
        a, b = map(int, input().split())
        G[a].append(b)
        G[b].append(a)

    q = int(input())

    for i in range(q):
        s, t = map(int, input().split())
        k = bfs(s, t)
        if k == -1:
            print("no")
        else:
            print("yes")


if __name__ == '__main__':
    main()

Python: V, E = map(int, input().split())
edge = [[] for _ in range(V)]
for _ in range(E):
    s, t = map(int, input().split())
    edge[s].append(t)
    edge[t].append(s)

group = [-1] * V
cnt = 0
for i in range(V):
    if group[i] == -1:
        group[i] = cnt
        stack = [i]
        while stack:
            v = stack.pop()
            for c in edge[v]:
                if group[c] == -1:
                    group[c] = cnt
                    stack.append(c)
        cnt += 1
for _ in range(int(input())):
    s, t = map(int, input().split())
    print('yes' if group[s] == group[t] else 'no')

Python: def warshall_floyd(w):
    inf = 1E+100
    n = len(w)
    d = w
    for k in range(n):
        d_new = [[inf for _ in range(n)] for _ in range(n)]
        for i in range(n):
            for j in range(n):
                d_new[i][j] = min(d[i][j], d[i][k] + d[k][j])
        d = d_new
    return d


inf = 1E+100
s = [int(x) for x in input().split()]
n = s[0]
m = s[1]
w = [[inf for _ in range(n)] for _ in range(n)]
for i in range(n):
    w[i][i] = 0
for _ in range(m):
    s = [int(x) for x in input().split()]
    w[s[0]][s[1]] = 1
    w[s[1]][s[0]] = 1

d = warshall_floyd(w)

q = int(input())
for _ in range(q):
    s = [int(x) for x in input().split()]
    u = s[0]
    v = s[1]
    if d[u][v] < inf:
        print("yes")
    else:
        print("no")

Python: # -*- coding: utf-8 -*-
from collections import deque

N, M = tuple(map(int, input().split()))
adj = [[] for n in range(N)]

for _ in range(M):
    inp = tuple(map(int, input().split()))
    adj[inp[0]].append(inp[1])
    adj[inp[1]].append(inp[0])

unsearched = set(range(N))
colors = {n:-1 for n in range(N)}
color = -1

for n in range(N):
    if colors[n] != -1:
        continue
    color += 1
    start = n
    
    que = deque([start])
    while len(que):
        q = que.pop()
        next_ = [i for i in adj[q] if colors[i] == -1]
        que.extendleft(next_)
        colors[q] = color
    
Q = int(input())

for i in range(Q):
    question = tuple(map(int, input().split()))
    if colors[question[0]] == colors[question[1]]:
        print("yes")        
    else:
        print("no")

Python: from collections import deque

V, E = map(int, input().split())
Edge = [[] for _ in range(V)]

for _ in range(E): #??£????????????
    u, v = map(int, input().split())
    Edge[u].append(v)
    Edge[v].append(u)
    
Group = [-1] * V #Group???????????????????????°?????????????±????????????????????????°?????????????????°??????????????????????????????
Cnt = 0 # Group???????????????????±????????????????

for i in range(V):
    if Group[i] == -1:
        Group[i] = Cnt
        Stack = deque([i])
        while Stack:
            v = Stack.pop()
            for c in Edge[v]:
                if Group[c] == -1:
                    Group[c] = Cnt
                    Stack.append(c)
        Cnt += 1

q = int(input())
for _ in range(q):
    s, t = map(int, input().split())
    print('yes' if Group[s] == Group[t] else 'no')

Python: #coding:utf-8
n, r = map(int,input().split())
Q = []
M = [[] for j in range(n)]
for i in range(r):
    i,j = map(int,input().split())
    M[i].append(j)
    M[j].append(i)


def search(person, target):
    data = M[person]
    for per in data:
        if per ==  target:
            global yes
            yes = 1
            print("yes")
            return
        if color[per] == "white":
            color[per] = "gray"
            search(per, target)
    color[person] = "black"

num = int(input())
for i in range(num):
    yes = 0
    color = ["white" for j in range(n)]
    person, target = map(int,input().split())
    search(person, target)
    if yes == 0:
        print("no")

Python: def dfs(r, c, g, color):
    s = [r]
    color[r] = c
    while len(s) != 0:
        u = s.pop()
        for i in range(len(g[u])):
            v = g[u][i]
            if color[v] is None:
                color[v] = c
                s.append(v)


def assignColor(n, g, color):
    color_id = 1
    for u in range(n):
        if color[u] is None:
            dfs(u, color_id, g, color)
            color_id += 1


n, m = [int(v) for v in input().split()]
g = [[] for i in range(n)]
for i in range(m):
    s, t = [int(v) for v in input().split()]
    g[s].append(t)
    g[t].append(s)

color = [None] * n
assignColor(n, g, color)

q = int(input())

for i in range(q):
    s, t = [int(v) for v in input().split()]
    if color[s] == color[t]:
        print('yes')
    else:
        print('no')