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#include <bits/stdc++.h>
using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int k, n1;
    cin >> k >> n1;

    vector<int> ns(k + 1, 0);
    vector<vector<int>> preds(k + 1);
    ns[1] = n1;
    preds[1].resize(n1);                 // wszystkie 0 – domyślnie

    int max_n = n1;
    for (int d = 2; d <= k; ++d) {
        int ni;
        cin >> ni;
        ns[d] = ni;
        max_n = max(max_n, ni);
        preds[d].resize(ni);
        for (int j = 0; j < ni; ++j) {
            cin >> preds[d][j];
        }
    }
    max_n += 5;

    vector<int> big_child(max_n + 1, 0);
    vector<int> big_ver(max_n + 1, 0);
    int version = 0;

    // ----- reqs od końca -----
    vector<vector<int>> reqs(k + 1);
    for (int d = k; d >= 1; --d) {
        if (d == k) {
            reqs[d].assign(ns[d], 1);
        } else {
            int nprev = ns[d];
            for (int i = 1; i <= nprev; ++i) big_child[i] = 0;

            for (int j = 0; j < ns[d + 1]; ++j) {
                int p = preds[d + 1][j];
                if (p > 0) big_child[p] += reqs[d + 1][j];
            }

            reqs[d].assign(nprev, 1);
            for (int m = 1; m <= nprev; ++m) {
                int s = big_child[m];
                if (s > 0) reqs[d][m - 1] = s;
            }
        }
    }

    // ----- new_reqs + num_leaves -----
    vector<int> new_req(k + 1, 0);
    vector<int> leaves(k + 1, 0);

    for (int d = 1; d <= k; ++d) {
        // new_req
        int nr = 0;
        for (int j = 0; j < ns[d]; ++j) {
            if (preds[d][j] == 0)
                nr += reqs[d][j];
        }
        new_req[d] = nr;

        // leaves
        if (d == k) {
            leaves[d] = ns[d];
        } else {
            ++version;
            int cnt = 0;
            for (int j = 0; j < ns[d + 1]; ++j) {
                int p = preds[d + 1][j];
                if (p > 0 && big_ver[p] != version) {
                    big_ver[p] = version;
                    ++cnt;
                }
            }
            leaves[d] = ns[d] - cnt;
        }
    }

    // ----- symulacja -----
    int pool = 0;
    int ans = 0;
    for (int d = 1; d <= k; ++d) {
        int need = new_req[d];
        if (pool < need) {
            int add = need - pool;
            ans += add;
            pool += add;
        }
        pool -= need;
        pool += leaves[d];
    }

    cout << ans << '\n';
    return 0;
}