#include <bits/stdc++.h>
using namespace std;

vector<int> adj[100];   //adjacency list (an array of vectors)
bool visited[100];      //to keep track which vertices are visited

void DFS(int v){
    //terminate function if vertex is visited
    if(visited[v]==true)    return;

    visited[v]=true;    //mark as visited
    cout<<v<<" ";       //prints out current vertex

    //for each vertex connected to current vertex, do DFS (recursive function)
    for(int i=0;i<adj[v].size();i++){
        int x=adj[v][i];
        if(!visited[x]) DFS(x);
    }
}

int main()
{
    int V,E; //specify no of vertices,V and edges,E
    cin>>V>>E;

    //create adjacency list (input E pairs of vertices that are connected by an edge)
    for(int i=0;i<E;i++){
        int a,b;
        cin>>a>>b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }

    DFS(0); //start DFS from vertex 0

    return 0;
}