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# Uses python3
import sys
def explore(v, adj, visited, postV, clock):
visited[v] = True
for w in adj[v]:
if visited[w] == False:
explore(w, adj, visited, postV, clock)
postV[v] = clock[0]
clock[0] = clock[0] + 1
def dfs(adj, visited, postV, clock):
for v in range(len(adj)):
if visited[v] == False:
explore(v, adj, visited, postV, clock)
def toposort(adj):
visited = [False] * len(adj)
order = []
postV = [0] * len(adj)
clock = [0]
dfs(adj, visited, postV, clock)
order = sorted(range(len(postV)), key=lambda k: postV[k], reverse=True)
return order
if __name__ == '__main__':
input = sys.stdin.read()
data = list(map(int, input.split()))
n, m = data[0:2]
data = data[2:]
edges = list(zip(data[0:(2 * m):2], data[1:(2 * m):2]))
adj = [[] for _ in range(n)]
for (a, b) in edges:
adj[a - 1].append(b - 1)
order = toposort(adj)
for x in order:
print(x + 1, end=' ')
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