#include <cstdio>
#include <vector>
#include <bitset>
#include <algorithm>

const int Nmax = 50005;

std::vector<int> G[Nmax],sol;
std::bitset<Nmax> used;
int N,M;

void DFS(int k)
{
    used[k] = true;
    for(std::vector<int>::iterator it = G[k].begin(); it != G[k].end(); ++it)
        if(!used[*it])
            DFS(*it);
    sol.push_back(k);
}

int main()
{
    freopen("sortaret.in","r",stdin);
    freopen("sortaret.out","w",stdout);

    scanf("%d%d",&N,&M);
    int a,b;
    for(int i = 1; i <= M; ++i)
    {
        scanf("%d%d",&a,&b);
        G[a].push_back(b);
        G[b].push_back(a);
    }
    DFS(1);
    reverse(sol.begin(),sol.end());
    for(int i = 1; i <= N; ++i)
        printf("%d ",sol[i-1]);

    return 0;
}