n, m = map(int, input().split())
adj = [[] for _ in range(n + 1)]
in_degree = [0] * (n + 1)
for _ in range(m):
    u, v = map(int, input().split())
    adj[u].append(v)
    in_degree[v] += 1
q = []
for i in range(1, n + 1):
    if in_degree[i] == 0:
        q.append(i)
head = 0
topsort = []
while head < len(q):
    u = q[head]
    head += 1
    topsort.append(u)    
    for v in adj[u]:
        in_degree[v] -= 1
        if in_degree[v] == 0:
            q.append(v)
if len(topsort) == n:
    print(*topsort)
else:
    print("-1")