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#include <bits/stdc++.h>
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using namespace std;
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const int N = 100010;
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const int M = 200010;
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int n, m;
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int h[N], e[M], ne[M], idx;
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int d[N];
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int q[N];
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void add(int a, int b) {
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    e[idx] = b;
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    ne[idx] = h[a];
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    h[a] = idx++;
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}
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bool topsort() {
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    int hh = 0;
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    int tt = -1;
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    for (int i = 1; i <= n; i++) {
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        if (d[i] == 0) q[++tt] = i;
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    }
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    while (hh <= tt) {
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        int t = q[hh++];
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        for (int i = h[t]; i != -1; i = ne[i]) {
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            int j = e[i];
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            d[j]--;
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            if (d[j] == 0) {
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                q[++tt] = j;
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            }
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        }
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    }
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    return tt == n - 1;
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}
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int main() {
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    cin >> n >> m;
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    memset(h, -1, sizeof h);
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    while (m--) {
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        int a, b;
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        cin >> a >> b;
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        add(a, b);
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        d[b]++;
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    }
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    if (topsort()) {
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        for (int i = 0; i < n; i++) {
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            cout << q[i] << " ";
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        }
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        cout << endl;
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    } else {
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        cout << "存在环，无拓扑序列" << endl;
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    }
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    return 0;
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}