#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define MAX 50005
using namespace std;

ifstream f("sortaret.in");
ofstream g("sortaret.out");

vector <vector<int> > G(MAX);
vector <int> viz(MAX);
int n, m;
queue <int> q;
void DFS(int s)
{
    viz[s] = 1;
    for (auto i: G[s])
    {
        if (!viz[i])
        {
            q.push(i);
            DFS(i);
        }
    }
}
int main()
{
    f >> n >> m;

    for (int i = 1; i <= m; i++)
    {
        int x, y;

        f >> x >> y;
        G[x].push_back(y);
    }
    DFS(1);
    g << 1 << " ";
    while(!q.empty())
    {
        g << q.front() << " ";
        q.pop();
    }

    return 0;
}