#include <iostream>
#include <vector>
#include <fstream>
using namespace std;

ifstream fin("sortaret.in");
ofstream fout("sortaret.out");

const int noduriMax = 100000;
vector <int> muchii[noduriMax];
bool used[noduriMax];
int n, m;
vector <int> noduri;

void dfs(int nod)
{
	used[nod] = true;
	noduri.push_back(nod);
	for (int i = 0; i < muchii[nod].size(); ++i)
	{
		int vecin = muchii[nod][i];
		if (used[vecin] == false)
			dfs(vecin);
	}
}

int main()
{
	fin >> n >> m;
	for (int i = 1; i <= m; ++i)
	{
		int x, y;
		fin >> x >> y;
		muchii[x].push_back(y);
		muchii[y].push_back(x);
	}
	dfs(1);
	for (int i = 0; i < noduri.size(); ++i)
		fout << noduri[i] << ' ';

}