#include<bits/stdc++.h>
using namespace std;

const int N = 100005;
int e[N], ne[N], h[N], idx;
int n, m, d[N];
queue<int> q, q1;

void add (int a, int b) {
    e[idx] = b, ne[idx] = h[a]; h[a] = idx++;
}

bool topsort () {
    for (int i = 1; i <= n; i++) {
        if (!d[i]) q.push(i);
    }

    while (!q.empty()) {
        int t = q.front(); q.pop(); q1.push(t);
        for (int i = h[t]; i != -1; i = ne[i]) {
            int j = e[i];
            if (--d[j] == 0) q.push(j);
        }
    }
    int s = q1.size();

    return s == n;
}

int main (void) {
    cin >> n >> m;
    memset(h, -1, sizeof(h));
    for (int i = 0; i < m; i++) {
        int a, b;
        cin >> a >> b;
        add(a, b); d[b]++;
    }

    if (!topsort()) puts("-1");
    else {
        while (!q1.empty()) {
            int t = q1.front();
            cout << t << " ";
            q1.pop();
        }
    }

}