#include <bits/stdc++.h>

using namespace std;

ifstream fin("sortaret.in");
ofstream fout("sortaret.out");

int n, m, x, y;
vector<int> a[50001];

void sorttop(int i) {
    sort(a[i].begin(), a[i].end());

    for (int x : a[i]) {
        fout << x << " ";
    }
    for (int x : a[i]) {
        sorttop(x);
    }
}

int main() {
    fin >> n >> m;
    for (int i = 0; i < m; i++) {
        fin >> x >> y;
        a[x].push_back(y);
    }

    fout << "1 ";
    sorttop(1);
}