#include <iostream>
#include <algorithm>
#include <vector>
#include <deque>
using namespace std;
vector<vector<int>> adj;
vector<bool> used;
//
void dfs(int idx){
    if(used[idx]) return;
    used[idx] = true;  // 标记已访问
    cout << idx + 1 << " ";
    
    for(auto x : adj[idx]){
        dfs(x);
    }
}

int main(){
	int v, e;
	cin >> v >> e;
	adj.resize(v);
	used.resize(v, false); 
	for(int i = 0; i < e; i++){
		int a, b;
		cin >> a >> b;
		adj[a - 1].push_back(b - 1);
	}
	for(int i = 0; i < v; i++){
		sort(adj[i].begin(), adj[i].end());
	} 
	dfs(0);
	fill(used.begin(), used.end(), false);
	
	cout << endl;
	//bfs
	deque<int> q;
	q.push_back(0);
	used[0] = true;
	while(!q.empty()){
    	int top = q.front(); q.pop_front(); // 注意这里用 front()
    	cout << top + 1 << " "; 
    	for(auto x : adj[top]){
        	if(!used[x]){
            	used[x] = true;  // 标记访问
            	q.push_back(x);
        	}
    	}
	}
	return 0;
}