#include <fstream>
#include <vector>
#include<algorithm>
using namespace std;

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

int n,k,i,p,m,x,y,nr=0;
int v[100010];
long long s;
vector <int>l[100010];

void dfs(int nod){
    int i;
    v[nod]=1;
    fout<<nod<<" ";
    for(i=0;i<l[nod].size();i++){
        if(v[l[nod][i]]==0){
            dfs(l[nod][i]);
        }
    }

}

int main(){
    fin>>n>>m;
    for(i=1;i<=m;i++){
        fin>>x>>y;
        l[x].push_back(y);
        l[y].push_back(x);
    }
    for (int i=1;i<=n; i++)
        sort(l[i].begin(), l[i].end());
    for(i=1;i<=n;i++){
            if(v[i]==0){
                dfs(i);

            }
    }




}