#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

vector<int>v1[50010],rez;
bool vf[50010];

void topSort(int x){
    vf[x]=1;
    rez.push_back(x);
    for(int i=0;i<v1[x].size();i++){
        if(vf[v1[x][i]] == 0)
            topSort(v1[x][i]);
    }
}

int main()
{
    int n,m,x,y;
    fin>>n>>m;
    for(int i =0;i<m;i++){
        fin>>x>>y;
        v1[x].push_back(y);
        v1[y].push_back(x);
    }
    for(int i=1;i<=n;i++){
        if(vf[i]==0)
            topSort(i);
    }
    for(int i=0;i<rez.size();i++)
        fout<<rez[i]<<' ';
    return 0;
}