#include<bits/stdc++.h>
using namespace std;
int graph[1001][1001];
int visit[1001];
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);
}
 

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