#include <fstream>
#include <algorithm>
#include <bitset>

using namespace std;

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

int n, m;
vector<pair<int, int>> v[50010];
bitset<50010> use;

int main() {
    fin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int x, y;
        fin >> x >> y;
        v[x].push_back(make_pair(y, i));
    }

    for (int i = 1; i <= n; i++)
        sort(v[i].begin(), v[i].end());

    for (int i = 1; i <= n; i++)
        for (auto it:v[i]) {
            fout << it.second << " ";
            use[it.second] = 1;
        }

    for (int i = 1; i <= n; i++)
        if (!use[i])
            fout << i << " ";
    return 0;
}