//1502

#include <stdio.h>

#include <string.h>

#include <queue>

using namespace std;

#define N 10

int g[N][N],bz[N],n,m,t;

queue <int> q;

void BFS(int cur)

{   int j;

    bz[cur]=1;  q.push(cur);

    while (!q.empty())

    {   cur=q.front(); printf("%d", cur);t++;

      if(t==n)printf("\n");

       else printf(" ");

       q.pop();

        for (j=1;j<=N;j++)

         if (bz[j]==0 && g[cur][j]==1) {  q.push(j);  bz[j]=1;  }

    }

}

void input()

{   int i,j,f;

    scanf("%d%d",&n,&m);

    for (int i=1; i<=m; i++)

    {   scanf("%d%d",&f,&t); g[f][t]=g[t][f]=1; }

}

int main()

{   memset(g,0,sizeof(g));  memset(bz,0,sizeof(bz));

    input();    BFS(0);

} 

**************************************************************************************************************

//1502

#include <iostream>

#include <cstring>

#include <queue>

#define N 100

using namespace std;

int map[N][N],bz[N];

int n,m,flag;

queue <int> my;

void bfs(int s)

{    int t,i;

    bz[s]=1;

    my.push(s);

    while (!my.empty())

    {    t=my.front();

        my.pop();

        if (flag==0)

        {  cout<<t; flag=1;}

        else cout<<" "<<t;

        for (i=0; i<n; i++)

        {

            if (map[t][i]==1 && bz[i]==0)

            {    bz[i]=1;

                my.push(i);

            }

        }

    }

}

int main()

{

    int x,y;

    cin>>n>>m;

    memset(map,0,sizeof(map));

    memset(bz,0,sizeof(bz));

    while (m--)

    {

        cin>>x>>y;

        map[x][y]=map[y][x]=1;

    }

     flag=0;

    bfs(0);

     cout<<endl;

    return 0;

}

*******************************************************************************************************

//1502

#include <iostream>

#include <queue>

using namespace std; 

queue <int> T; 

int a,b,tu[100][100],bz[100],v=0;  

void BFS(int k)

{   int t,i;

    T.push(k);

    bz[k]=1;

    while(!T.empty())

    {

        t=T.front();

        v++;

        T.pop();

        if(v!=a)cout<<t<<" ";

          else cout<<t<<endl;

        for(i=0;i<a;i++)

            if(tu[t][i]==1&&bz[i]==0)

            {   bz[i]=1;

                T.push(i);

            }

    }

}   

int main()

{

    int i=0,b,x,y,ans;

    cin>>a>>b;

    while (i<b)

    {  cin>>x>>y;

       tu[x][y]=tu[y][x]=1;

       i++;

    }

    BFS(0);

    return 0;

}