#include <iostream>
#include <vector>
#include <queue>
using namespace std;
const int INF = 1e9;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
cin>>n;
vector<vector<int>> adj(n + 2);
for (int i = 1; i <= n; ++i) {
int sd;
cin >> sd;
for (int j = 0; j < sd; ++j) {
int az;
cin >> az;
adj[az].push_back(i);
}
}
long long mini = -1;
for (int i = 1; i <= n; ++i) {
vector<int> dist(n + 1, INF);
queue<int> q;
dist[i] = 0;
q.push(i);
bool moz = true;
long long ob = 0;
while (!q.empty()) {
int u = q.front();
q.pop();
ob += dist[u] + 1;
for (int v : adj[u]) {
if (dist[v] == INF) {
dist[v] = dist[u] + 1;
q.push(v);
}
}
}
for (int j = 1; j <= n; ++j) {
if (dist[j] == INF) {
moz = false;
break;
}
}
if (moz==true) {
if (mini == -1 || ob < mini) {
mini = ob;
}
}
}
cout << mini;
return 0;
}
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