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#ifdef DEBUG
#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#else
#define debug(...) 228
#endif


typedef long long ll;
typedef long double ld;

#define pb push_back
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)

vector<int> read_vec(int n) {
    vector<int> v(n);
    for (int& t : v) cin >> t;
    return v;
}

template<typename T>
inline void upd_max(T& a, T b) {
    if (a < b) {
        a = b;
    }
}

template<typename T>
inline void upd_min(T& a, T b) {
    if (a > b) {
        a = b;
    }
}

int k;
const int maxN = 1e6 + 10;
int sz[maxN];
vector<int> g[maxN];
int dp[maxN];
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef DEBUG
    freopen("input.txt", "r", stdin);
#endif
    cin >> k;
    int N = 0;
    FOR(i, 0, k) {
        cin >> sz[i];
        if (i > 0) {
            FOR(j, 0, sz[i]) {
                int who;
                cin >> who;
                --who;
                if (who != -1) {
                    g[who + N - sz[i - 1]].emplace_back(N + j);
                }
            }
        }
        N += sz[i];
    }
    for (int i = N - 1; i >= 0; i--) {
        for (int j : g[i]) {
            dp[i] += dp[j];
        }
        upd_max(dp[i], 1);
    }
    int cur = 0;
    ll ans = 0;
    FOR(i, 0, k) {
        ll s = 0;
        FOR(it, cur, cur + sz[i]) s += dp[it];
        cur += sz[i];
        upd_max(ans, s);
    }
    cout << ans << '\n';
    return 0;
}