#include <bits/stdc++.h>
using namespace std;
int graph[1001][1001];
int visit[1001]; //globally declaring an array means array value is 1;
int n,e;
void DFS(int start)
{
    //initial step
    visit[start]=1;
    cout<<start<<" ";
    stack<int>stk;
    stk.push(start);

    //repeating step
    while(!stk.empty())
    {
      for(int j=1;j<=n;j++)
      {
        int x= stk.top();
            if(visit[j]==0 && graph[x][j]!=0)
            {
                visit[j]=1;
                cout<<j<<" ";
                stk.push(j);
                j=1;
            }
        }
        stk.pop();
    }
}

int main()
{
cin>>n>>e;
int u,v;
for(int i=1;i<=e;i++)
{
    cin>>u>>v;
    graph[u][v]=1;
    graph[v][u]=1;
}
DFS(1);



return 0;
}