Buggy python submission (verdict: Runtime Error):
import sys
sys.setrecursionlimit(10**5)

n, m = map(int, input().split())
xyz = [[] for i in range(n+1)]
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append(y)
    xyz[y].append(x)
    
ans = 0
visited = [False]*(n+1)
def dfs(x):
    visited[x] = True
    for y in xyz[x]:
        if not visited[y]:
            dfs(y)

for x in range(1, n+1):
    if visited[x]:
        continue
    dfs(x)
    ans += 1
    
# print(visited)
print(ans)


Fixed submission:
from collections import deque

n, m = map(int, input().split())
xyz = {i:[] for i in range(1, n+1)}
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append((x, y, z))
    xyz[y].append((y, x, z))

connects = [0]*(n+1)
group = 1
for i in range(1, n+1):
    if connects[i] > 0:
        continue
    if len(xyz[i]) == 0:
        connects[i] = group
        group += 1
        continue

    que = deque(xyz[i])
    connects[i] = group
    while len(que) > 0:
        x, y, z = que.popleft()
        connects[y] = group
        for xn, yn, zn in xyz[y]:
            if connects[yn] > 0:
                pass
            else:
                que.append((xn, yn, zn))
    group += 1
    
# print(connects)
print(max(connects))

Buggy python submission (verdict: Runtime Error):
n, m = map(int, input().split())
xyz = [[] for i in range(n+1)]
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append(y)
    xyz[y].append(x)
    
ans = 0
visited = [False]*(n+1)
def dfs(x):
    visited[x] = True
    for y in xyz[x]:
        if not visited[y]:
            dfs(y)

for x in range(1, n+1):
    if visited[x]:
        continue
    dfs(x)
    ans += 1
    
# print(visited)
print(ans)


Fixed submission:
from collections import deque

n, m = map(int, input().split())
xyz = {i:[] for i in range(1, n+1)}
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append((x, y, z))
    xyz[y].append((y, x, z))

connects = [0]*(n+1)
group = 1
for i in range(1, n+1):
    if connects[i] > 0:
        continue
    if len(xyz[i]) == 0:
        connects[i] = group
        group += 1
        continue

    que = deque(xyz[i])
    connects[i] = group
    while len(que) > 0:
        x, y, z = que.popleft()
        connects[y] = group
        for xn, yn, zn in xyz[y]:
            if connects[yn] > 0:
                pass
            else:
                que.append((xn, yn, zn))
    group += 1
    
# print(connects)
print(max(connects))

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque

n, m = map(int, input().split())
xyz = [[] for i in range(n+1)]
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append(y)
    xyz[y].append(x)
    
ans = 0
visited = [False]*(n+1)
for x in range(1, n+1):
    if visited[x]:
        continue

    que = deque(xyz[x])
    while len(que) > 0:
        y = que.popleft()
        visited[y] = True
        for yn in xyz[y]:
            if not visited[yn]:
                que.append(yn)
    ans += 1
    
# print(visited)
print(ans)


Fixed submission:
from collections import deque

n, m = map(int, input().split())
xyz = {i:[] for i in range(1, n+1)}
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append((x, y, z))
    xyz[y].append((y, x, z))

connects = [0]*(n+1)
group = 1
for i in range(1, n+1):
    if connects[i] > 0:
        continue
    if len(xyz[i]) == 0:
        connects[i] = group
        group += 1
        continue

    que = deque(xyz[i])
    connects[i] = group
    while len(que) > 0:
        x, y, z = que.popleft()
        connects[y] = group
        for xn, yn, zn in xyz[y]:
            if connects[yn] > 0:
                pass
            else:
                que.append((xn, yn, zn))
    group += 1
    
# print(connects)
print(max(connects))

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque

n, m = map(int, input().split())
xyz = {i:[] for i in range(1, n+1)}
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append((x, y, z))
    xyz[y].append((y, x, z))

connects = [0]*(n+1)
group = 1
for i in range(1, n+1):
    if connects[i] > 0:
        continue
    if len(xyz[i]) == 0:
        connects[i] = group
        group += 1
        continue

    que = deque(xyz[i])
    connects[i] = group
    while len(que) > 0:
        x, y, z = que.popleft()
        connects[y] = group
        for xn, yn, zn in xyz[y]:
            if connects[yn] > 0:
                pass
            else:
                que.append((xn, yn, zn))
    group += 1
    
# print(connects)
print(max(connects))


Fixed submission:
from collections import deque

n, m = map(int, input().split())
xyz = {i:[] for i in range(1, n+1)}
for _ in range(m):
    x, y, z = map(int, input().split())
    xyz[x].append((x, y, z))
    xyz[y].append((y, x, z))

connects = [0]*(n+1)
group = 1
for i in range(1, n+1):
    if connects[i] > 0:
        continue
    if len(xyz[i]) == 0:
        connects[i] = group
        group += 1
        continue

    que = deque(xyz[i])
    connects[i] = group
    while len(que) > 0:
        x, y, z = que.popleft()
        connects[y] = group
        for xn, yn, zn in xyz[y]:
            if connects[yn] > 0:
                pass
            else:
                que.append((xn, yn, zn))
    group += 1
    
# print(connects)
print(max(connects))