#include <fstream>
#include <vector>

using namespace std;

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

int n, m;
vector<int> v[50005];
vector<int> postordine;
bool viz[50005] = { false };

void DFS(int x) {
    viz[x] = true;
    for (int i = 0; i < v[x].size(); i++) {
        if (!viz[v[x][i]]) {
            DFS(v[x][i]);
        }
    }
    postordine.push_back(x);
}

int main(int argc, char *argv[]) {
    fin >> n >> m;
    int x, y;
    for (int i = 0; i < m; i++) {
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    DFS(1);
    for (int i = postordine.size() - 1; i >= 0; i--) {
        fout << postordine[i] << " ";
    }
    return 0;
}