20分WA

#include <iostream>
#include <queue>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;

int n, m, r, l;
bool vis[100001];
vector<int> map[100001];
queue<int> q;

void dfs(int k)
{
	cout << k << ' ';
	for (size_t i = 0; i < map[k].size(); ++i)
		if (!vis[map[k][i]])
			vis[map[k][i]] = 1, dfs(map[k][i]);
}

void bfs()
{
	vis[1] = 1;
	q.push(1);
	while (q.size())
	{
		int f = q.front();
		q.pop();
		cout << f << ' ';
		for (size_t i = 0; i < map[f].size(); ++i)
			if (!vis[map[f][i]])
				vis[map[f][i]] = 1, q.push(map[f][i]);
	}
}

int main()
{
	cin >> n >> m;
	for (int i = 1; i <= m; ++i)
		cin >> r >> l, map[r].push_back(l);
	for (int i = 1; i <= n; ++i)
		sort(map[i].begin(), map[i].end());
	dfs(1);
	cout << endl;
	memset(vis, 0, sizeof(vis));
	bfs();
}