#include<fstream>
#include<vector>
using namespace std;
ifstream f("sortaret.in");
ofstream g("sortaret.out");
int n,m,x,y,viz[50002];
vector<int> v[50002],sol;
void dfs(int i)
{
	if(!viz[i])
	{
		g<<i<<" ";
		viz[i]=1;
		for(unsigned int j=0;j<v[i].size();j++)
		{
			dfs(v[i][j]);
		}
	}
}
int main()
{
	f>>n>>m;
	for(int i=1;i<=m;i++)
	{
		f>>x>>y;
		v[x].push_back(y);
		v[y].push_back(x);
	}
	dfs(1);
}