/*#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize ("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")*/
#include<bits/stdc++.h>
#include <cstdlib>
/*#include <bits/extc++.h>
using namespace std;
using namespace __gnu_pbds;
template<class T>
using oset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
/**/
//typedef int ll;
typedef long long ll;
typedef unsigned long long ull;
typedef __int128 vll;
typedef unsigned __int128 uvll;
ll _i=0;
#define ffn(x) _i=x
#define llll std::pair<ll , ll>
#define stitr set<ll>::iterator
#define fora(y,x) for(ll y=_i;x>y;y++)
#define pb push_back
#define pf push_front
#define halo cout << "hello\n"
#define fi first
#define sec second
#define all(a) a.begin() , a.end()
const ll limit = 1e18 + 7;
const ll ous = 5007;
const ll dx[4] = {1 , 0 , 0 , -1} , dy[4] = {0,1,-1,0};
std::vector<ll> adj[ous];
ll s = 0 , n;
ll vis[ous];
ll bfstest(ll x){
memset(vis , 0 , sizeof(vis));
s = 0;
ll sum = 0;
std::queue<llll> qu;
qu.push({x , 1});
vis[x] = 1;
while(!qu.empty()){
llll a = qu.front();
//std::cout << a.fi << " " << a.sec << "\n";
qu.pop();
sum+=a.sec;
s++;
for(auto j:adj[a.fi]){
if(vis[j] == 0){
vis[j] = 1;
qu.push({j , a.sec + 1});
}
}
}
if(s == n){
return sum;
}
return -1;
}
void solve(){
std::cin >> n;
for(ll i = 1;n>=i;i++){
ll k;std::cin >> k;
fora(j , k){
ll x;std::cin >> x;
adj[x].pb(i);
}
}
ll rt = limit;
fora(i , n){
ll s = bfstest(i + 1);
rt = std::min(rt , (s == -1 ? limit :s));
//std::cout << s << " " << i+1 << "\n";
}
if(rt == limit){
rt = -1;
}
std::cout << rt << "\n";
return;/**/
}
signed main(){
std::ios_base::sync_with_stdio(false);std::cin.tie(NULL);
ll t=1;
//std::cin >> t;
ll o = 1;
while(t--){
//cout << "Case " << o++ << ":\n";
solve();
}
return 0;
}
