Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n


def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n


def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(10000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(20000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(100000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(1000000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(10000000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(100000000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(10000000000000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

isVisited = [False] * n

CC = [None] * n

import sys
sys.setrecursionlimit(1000000000)

def dfs(u, group):
    isVisited[u] = True
    CC[u] = group
    for v in adj[u]:
        if not isVisited[v]:
            dfs(v, group)

def makeCC(group):
    for i in range(n):
        if not isVisited[i]:
            dfs(i, group)
            group += 1

def isConnected(v1, v2):
    if CC[v1] == CC[v2]:
        print('yes')
    else:
        print('no')


makeCC(0)


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)

Fixed submission:
n, m = map(int, input().split())

adj = [[] for i in range(n)]

for i in range(m):
    s, t = map(int, input().split())
    adj[s].append(t)
    adj[t].append(s)

groups = [None] * n


def dfs(u, group_num):
    path = []
    path.append(u)
    groups[u] = group_num
    while path:
        u = path[-1]
        if adj[u]:
            v = adj[u].pop(0)
            if not groups[v]:
                groups[v] = group_num
                path.append(v)
        else:
            path.pop()


g_n = 1
for i in range(n):
    if not groups[i]:
        dfs(i, g_n)
        g_n += 1

def isConnected(v1, v2):
    if groups[v1] == groups[v2]:
        print('yes')
    else:
        print('no')


q = int(input())

for i in range(q):
    s, t = map(int, input().split())
    isConnected(s, t)