#include <bits/stdc++.h>

using namespace std;

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

int n,i,a,b,mark[205],m,vecin,st;
vector <int> v[205];
vector <int> sol;

int DFS(int start){
    st = start;
    if(v[start].size() > 1){
    sol.push_back(start);
    for(int i=0;i<v[start].size();i++){
        vecin = v[start][i];
        v[start].erase(v[start].begin());
        v[v[start][i]].erase(v[v[start][i]].begin());
        DFS(vecin);

    }
    }
    else{
    sol.push_back(start);
    }
}



int main()
{
fin>>n>>m;
while(m--){
    fin>>a>>b;
    v[a].push_back(b);
    v[b].push_back(a);;
}
DFS(1);
sol.push_back(v[st][0]);
for(i=0;i<sol.size();i++){
    fout << sol[i] << " ";
}
    return 0;
}