图的遍历

#include <iostream>
#include <queue>
#include <cstring>
#include <vector>
#include <algorithm>
using namespace std;
vector<int> adj[100001];
int check[100001];
queue<int> q;
void dfs(int u)
{
    if (check[u])
        return;
    check[u] = 1;
    cout << u << " ";
    for (int i = 0; i < adj[u].size(); i++)
    {
        int v = adj[u][i];
        dfs(v);
    }
}
void bfs(int u)
{
    q.push(u);
    check[u] = 1;
    while (!q.empty())
    {
        int v = q.front();
        q.pop();
        cout << v << " ";
        for (int i = 0; i < adj[v].size(); i++)
        {
            int w = adj[v][i];
            if (!check[w])
            {
                q.push(w);
                check[w] = 1;
            }
        }
    }
}
int main()
{
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v); // 邻接表
    }
    for (int i = 1; i <= n; i++)
    {
        sort(adj[i].begin(), adj[i].end());
    }
    dfs(1);
    cout << endl;
    memset(check, 0, sizeof(check));
    bfs(1);
    return 0;
}
// 5 6 点 边
// 1 2
// 2 3
// 2 5
// 3 5
// 5 4
// 5 1