#include<iostream.h>
int a[10][10],c[10],viz[10],i;
void main(){int n,m,x,y,ib,ie;
	    cin>>n;
	    cin>>m;
	    for(i=1;i<=n;i++)
	    {cin>>x>>y;
	     a[x][y]=a[y][x]=1;}
	     ib=ie=1;
	     c[ib]=1;
	     viz[i]=1;
	     while(ib<=ie){ for(i=1;i<=n;i++)
				if((a[c[ib]][i]==1) && (viz[i]==0))
				  {ie++;c[ie]=i;viz[i]=1;}
	     cout<<c[ib];
	     ib++;}}