调不出来qwq

#include <bits/stdc++.h>
using namespace std;

int n, a[610], b[610], ind[610], cnt;
vector<int> p[610];

void topo(){
	queue<int> q;
	for(int i = 1 ; i <= n ; i ++){
		if(!ind[a[i]]){
			q.push(a[i]);
		}
	}
	while(!q.empty()){
		int x = q.front();
		q.pop();
		if(!b[x]) continue;
		for(int i = 0 ; i < p[x].size() ; i ++){
			ind[p[x][i]] --;
			if(!ind[p[x][i]]){
				q.push(p[x][i]);
			}
		}
		cnt ++;		
	}
}

int main(){
	cin >> n;
	for(int i = 1 ; i <= n ; i ++){
		int x, t;
		cin >> x >> t;
		a[i] = x;
		b[x] = i;
		for(int j = 1 ; j <= t ; j ++){
			int tmp;
			cin >> tmp;
			p[i].push_back(tmp);
			ind[tmp] ++;
		}
	} 
	topo();        
	if(cnt == n){
		cout << "YES" << endl;
	}
	else{
		cout << n - cnt << endl;
	}
	return 0;
}