#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
queue<int> Q;           //queue of incoming vertices to check

void BFS(int v){
    Q.push(v);          //insert root vertex (vertex 0)
    visited[v]=true;    //mark as visited

    while(!Q.empty()){          //repeat while the queue is not empty

        int now=Q.front();      //take frontmost vertex as current vertex
        cout<<now<<" ";         //prints out current vertex
        Q.pop();                //remove the frontmost element

        //check each vertex connected to current vertex
        for(int i=0;i<adj[now].size();i++){
            int x=adj[now][i];
            if(!visited[x]){        //if vertex is not visited, add it to the (back of) queue
                visited[x]=true;
                Q.push(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);
    }

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

    return 0;
}