vector存储+ bfs 版

#include<iostream>
#include<vector>
#include<queue>
using namespace std;
int main()
{
    int n, m;
    cin >> n >> m;
    vector<vector<int>>graph(n + 1);
    while(m --)
    {
        int id, k;
        cin >> id >> k;
        while(k --)
        {
            int v;
            cin >> v;
            graph[id].push_back(v);
        }
    }
    queue<int>q;
    vector<bool>visited(n + 1, false);
    q.push(1);
    visited[1] = 0;
    int c = 0;
    while(q.size())
    {
        int s = q.size();
        int count = 0;
        while(s --)
        {
            auto t = q.front();
            q.pop();
            int k = 0;
            int nn = graph[t].size();
            for(; k < nn; k ++)
            {
                if(!visited[graph[t][k]])
                {
                    q.push(graph[t][k]);
                    visited[graph[t][k]] = true;
                }
            }
            if(k == 0)count ++;
        }
        if(!c)
        {
            cout << count ;
            c ++;
        }
        else
        {
            cout << " " << count ;
        }

    }
    cout << endl;
    return 0;
}