#include <fstream>
#include <bitset>
#include <vector>

using namespace std;

ifstream f("sortaret.in");
ofstream g("sortaret.out");

vector <int> A[50001];
bitset <50001> vi;
int n,a,b,i,m,c[50001];

void dfs(int nod) {
    vi[nod]=1;c[++c[0]]=nod;
    vector<int>::iterator it;
    for (it=A[nod].begin();it!=A[nod].end();it++)
        if (vi[*it]==0)
            dfs(*it);

    return ;
}


int main () {
    f >> n >> m;
    for (i=1;i<=m;i++) {
        f >> a >> b;
        A[a].push_back(b);
        A[b].push_back(a);
    }
    for (i=1;i<=n;i++)
        if (vi[i]==0)
            dfs(i);
    for (i=1;i<=n;i++) g << c[i] << ' ';
    f.close();g.close();
    return 0;
}