#include <bits/stdc++.h>

using namespace std;

const int maxN = 100005, inf = 1e9;
int n, m, indeg[maxN];
vector <int> G[maxN];

int main() {
#ifdef LOCAL
    freopen("test.in", "r", stdin);
    freopen("test.out", "w", stdout);
#else
    freopen("sortaret.in", "r", stdin);
    freopen("sortaret.out", "w", stdout);
#endif
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        int x, y;
        cin >> x >> y;
        G[x].push_back(y);
        indeg[y]++;
    }

    vector <int> sortare;
    for (int i = 1; i <= n; i++) {
        if (indeg[i] == 0) {
            sortare.push_back(i);
        }
    }
    for (int i = 0; i < sortare.size(); i++) {
        int nod = sortare[i];
        cout << nod << ' ';
        for (int vecin : G[nod]) {
            indeg[vecin]--;
            if (indeg[vecin] == 0) {
                sortare.push_back(vecin);
            }
        }
    }
    return 0;
}