Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for _ in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        root = i
        break
d = [0] * n
s = [root]
while s:
    p = s.pop()
    for node in g[p]:
        d[node] = max(d[node], d[p] + 1)
        s.append(node)
ans = [0] * n
for i in range(n):
    for node in g[i]:
        if d[node] == d[i] + 1:
            ans[node] = i + 1
for x in ans:
    print(x)


Fixed submission:
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for _ in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        root = i
        break
d = [0] * n
s = [root]
while s:
    p = s.pop()
    for node in g[p]:
        inv[node] -= 1
        if inv[node] == 0:
            d[node] = max(d[node], d[p] + 1)
            s.append(node)
ans = [0] * n
for i in range(n):
    for node in g[i]:
        if d[node] == d[i] + 1:
            ans[node] = i + 1
for x in ans:
    print(x)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for i in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        q = deque([i])
        break
ans = [0] * n
while q:
    d = q.popleft()
    for node in g[d]:
        ans[node] = d + 1
        q.append(node)
for x in ans:
    print(x)


Fixed submission:
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for _ in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        root = i
        break
d = [0] * n
s = [root]
while s:
    p = s.pop()
    for node in g[p]:
        inv[node] -= 1
        if inv[node] == 0:
            d[node] = max(d[node], d[p] + 1)
            s.append(node)
ans = [0] * n
for i in range(n):
    for node in g[i]:
        if d[node] == d[i] + 1:
            ans[node] = i + 1
for x in ans:
    print(x)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for i in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        q = deque([i])
        break
ans = [0] * n
while q:
    d = q.popleft()
    for node in g[d]:
        ans[node] = d + 1
        q.append(node)
for x in ans:
    print(x)


Fixed submission:
n, m = map(int, input().split())
g = [[] for _ in range(n)]
inv = [0] * n
for _ in range(n - 1 + m):
    a, b = map(int, input().split())
    g[a - 1].append(b - 1)
    inv[b - 1] += 1
for i in range(n):
    if inv[i] == 0:
        root = i
        break
d = [0] * n
s = [root]
while s:
    p = s.pop()
    for node in g[p]:
        inv[node] -= 1
        if inv[node] == 0:
            d[node] = max(d[node], d[p] + 1)
            s.append(node)
ans = [0] * n
for i in range(n):
    for node in g[i]:
        if d[node] == d[i] + 1:
            ans[node] = i + 1
for x in ans:
    print(x)