#include<bits/stdc++.h>
using namespace std;
constexpr int _N = 3e5 + 5;
int n, m;
map<pair<int, int>, bool> H;
void AddEdge(int x, int y) { H[{x, y}] = H[{y, x}] = 1; }
bool Check(int x, int y) { return H.count({x, y}); }
signed main() {
   ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
   cin >> n >> m;
   for (int i = 1, x, y; i <= m; ++i)
      cin >> x >> y, AddEdge(x, y);
   vector<int> q1, q2;
   q1.emplace_back(1), q2.emplace_back(2);
   for (int i = 3; i <= n; ++i) {
      int x = -1, y = -1;
      if (!q1.empty()) x = q1.back();
      else { q1.emplace_back(i); continue; }
      if (!q2.empty()) y = q2.back();
      else { q2.emplace_back(i); continue; }
      if (Check(i, x)) q1.emplace_back(i);
      else if (!Check(i, y)) q2.emplace_back(i);
      else {
         if (Check(x, y)) {
            q2.pop_back();
            q1.emplace_back(y);
            q1.emplace_back(i);
         } else {
            q1.pop_back();
            q2.emplace_back(x);
            q2.emplace_back(i);
         }
      }
   }
   for (int x : q1) cout << x << ' ';
   for (int x : q2) cout << x << ' ';
   cout << '\n';
}