#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n; cin>>n;
vector<int> g[n + 1];
for (int i = 1; i <= n; i++){
int k; cin>>k;
while (k--){
int x; cin>>x;
g[x].pb(i);
}
}
int out = 1e9;
for (int i = 1; i <= n; i++){
vector<int> dist(n + 1, 1e9); dist[i] = 1;
queue<int> q; q.push(i);
while (!q.empty()){
int v = q.front(); q.pop();
for (int u: g[v]){
if (dist[u] == 1e9){
dist[u] = dist[v] + 1;
q.push(u);
}
}
}
int s = 0;
for (int j = 1; j <= n; j++){
if (dist[j] == 1e9){
s = -1;
}
s += dist[j];
}
if (s != -1){
out = min(out, s);
}
}
cout<<out<<"\n";
}
