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#include<cstdio>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<string>
#include<vector>
#include<cmath>
#include<bitset>
#include<unordered_map>

using namespace std;

typedef vector<int> VI;
typedef long long LL;
typedef vector<LL> VLL;
typedef pair<int, int> PII;
typedef vector<PII> VPII;

#define FOR(x, b, e) for(int x=b; x<=(e); ++x)
#define FORD(x, b, e) for(int x=b; x>=(e); --x)
#define REP(x, n) for(int x=0; x<(n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FOREACH(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define PB push_back
#define ST first
#define ND second

VLL state(2);

bool isReseted() {
    return state[0] == 0 && state[1] == 0;
}

void setState(int i, bool val) {
    if (val) state[i / 50] &= ~(1 << (i % 50));
    else state[i / 50] |= (1 << (i % 50));
}

int main() {
	ios_base::sync_with_stdio(0);
    cin.tie(NULL); cout.tie(NULL);
    int n;
    cin >> n;
    vector<VI> graph(n);
    REP(i, n) {
        int k, w;
        cin >> k;
        REP(j, k) {
            cin >> w;
            graph[i].PB(--w);
        }
    }
    VI belts(n);
    int round = 0;
    do {
        int v = 0;
        while (!graph[v].empty()) {
            int b = belts[v];
            belts[v] = (belts[v] + 1) % graph[v].size();
            setState(v, belts[v] == 0);
            v = graph[v][b];
        }
        round++;
    } while (!isReseted());
    cout << round << '\n';
    return 0;
}