#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;

int n, m;
int head[100010];
int to[100010];
int nxt[100010];
bool vis[100010];
int tmp = 0;

void addEdge(int x, int y)
{
	to[tmp] = y;
	nxt[tmp] = head[x];
	head[x] = tmp;
	tmp ++;
}

void dfs(int x)
{
	printf("%d ", x);
	vis[x] = true;
	for(int i = head[x]; i != -1; i = nxt[i])
	{
		if(! vis[to[i]])
		dfs(to[i]);
	}
}

int main()
{
	memset(head, -1, sizeof head);
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= m; i ++)
	{
		int x, y;
		scanf("%d%d", &x, &y);
		addEdge(x, y);
		addEdge(y, x);
	}
	dfs(1);
	return 0;
}