Buggy python submission (verdict: Runtime Error):
from collections import deque

def topological_sort(V, to):
    cnt = [0]*V
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = deque(i for i in range(V) if cnt[i]==0)
    res = []
    while len(Q) > 0:
        i = Q.popleft()
        res.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return s

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Fixed submission:
from collections import deque

def topological_sort(V, to):
    cnt = [0]*V
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = deque(i for i in range(V) if cnt[i]==0)
    res = []
    while Q:
        i = Q.popleft()
        res.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return res

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Buggy python submission (verdict: Time Limit Exceeded):
def topological_sort(V, to):
    cnt = [0]*V
    s = []
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = [i for i in range(V) if cnt[i]==0]
    while len(Q) > 0:
        i = Q[0]
        del Q[0]
        s.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return s

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Fixed submission:
from collections import deque

def topological_sort(V, to):
    cnt = [0]*V
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = deque(i for i in range(V) if cnt[i]==0)
    res = []
    while Q:
        i = Q.popleft()
        res.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return res

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Buggy python submission (verdict: Time Limit Exceeded):
def topological_sort(V, to):
    cnt = [0]*V
    s = []
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = []
    for i in range(V):
        if cnt[i] == 0:
            Q.append(i)
    while len(Q) > 0:
        i = Q[0]
        del Q[0]
        s.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return s

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Fixed submission:
from collections import deque

def topological_sort(V, to):
    cnt = [0]*V
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = deque(i for i in range(V) if cnt[i]==0)
    res = []
    while Q:
        i = Q.popleft()
        res.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return res

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Buggy python submission (verdict: Runtime Error):
N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)

Fixed submission:
from collections import deque

def topological_sort(V, to):
    cnt = [0]*V
    for i in range(V):
        for j in to[i]:
            cnt[j] += 1
    Q = deque(i for i in range(V) if cnt[i]==0)
    res = []
    while Q:
        i = Q.popleft()
        res.append(i)
        for k in to[i]:
            cnt[k] -= 1
            if cnt[k] == 0:
                Q.append(k)
    return res

N,M = map(int,input().split())
to = [[] for i in range(N)]
From = [[] for i in range(N)]
for i in range(N-1+M):
    x, y = list(map(int,input().split()))
    to[x-1].append(y-1)
    From[y-1].append(x-1)
s = topological_sort(N, to)
s = [(s[i],i) for i in range(N)]
s.sort()
for i in range(N):
    k = -1
    I = -1
    for j in From[i]:
        if k < s[j][1]:
            k = s[j][1]
            I = j
    print(I+1)