#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int n;
vector<int> children[5001];
bool vis[5001];
int dist[5001];
int main()
{
cin >> n;
for (int i = 1, k; i <= n; i++)
{
cin >> k;
for (int j = 0, par; j < k; j++)
{
cin >> par;
children[par].push_back(i);
}
}
ll ans = LLONG_MAX;
for (int root = 1; root <= n; root++)
{
queue<int> q;
q.push(root);
memset(vis, false, sizeof(vis));
vis[root] = true;
memset(dist, 0, sizeof(dist));
while (!q.empty())
{
int u = q.front();
q.pop();
for (const int &v : children[u])
if (!vis[v])
{
q.push(v);
vis[v] = true;
dist[v] = dist[u] + 1;
}
}
bool connected = true;
for (int i = 1; i <= n; i++)
connected &= vis[i];
if (!connected)
continue;
ll res = 0;
for (int i = 1; i <= n; i++)
res += 1 + dist[i];
ans = min(ans, res);
}
cout << (ans == LLONG_MAX ? -1 : ans) << '\n';
return 0;
}
