题解

#include<bits/stdc++.h>;
using namespace std;
int a,maps[1005][1005],n[1005],cmd=1;
void bfs(){
	queue<int>q;
	q.push(0);
	n[0]=1;
	while(!q.empty()){
		int k=q.front();
		q.pop();
		for(int i=1;i<=maps[k][0];i++){
			if(n[maps[k][i]])continue;
			n[maps[k][i]]=1;
			q.push({maps[k][i]});
			cmd++;
		}
	}
}
int main(){
	int b;
	cin>>a;
	for(int i=0;i<a;i++){
		cin>>b;
		maps[i][0]=b;
		for(int j=1;j<=b;j++){
			cin>>maps[i][j];
		}
	}
	bfs();
	cout<<cmd;
    return 0;
}