#include <bits/stdc++.h>

using namespace std;

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

int n,i,a,b,mark[205],d[1005][1005],m;
vector <int> v[205];
vector <int> sol;

void DFS(int start){
    for(int i=0;i<v[start].size();i++){
        if(d[start][v[start][i]]){
        d[start][v[start][i]]--;
        d[v[start][i]][start]--;
        DFS(v[start][i]);
        }
    }
    sol.push_back(start);
}



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

    return 0;
}