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#include <iostream>
#include <vector>
using namespace std;

const int MAX = 500005;

vector<int> g[MAX];
int f[MAX];
int n[MAX];
int off[MAX];
bool root[MAX];

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

    int k;
    cin >> k;

    int idx = 0;

    for (int d = 1; d <= k; d++) {
        cin >> n[d];
        off[d] = idx;

        for (int i = 1; i <= n[d]; i++) {
            int u = off[d] + i;

            if (d == 1) {
                root[u] = true;
            } else {
                int p;
                cin >> p;

                if (p == 0) {
                    root[u] = true;
                } else {
                    int par = off[d - 1] + p;
                    g[par].push_back(u);
                }
            }
        }
        idx += n[d];
    }

    for (int d = k; d >= 1; d--) {
        for (int i = 1; i <= n[d]; i++) {
            int u = off[d] + i;

            if (g[u].empty()) {
                f[u] = 1;
            } else {
                f[u] = 0;
                for (int v : g[u]) {
                    f[u] += f[v];
                }
            }
        }
    }

    long long ans = 0;
    int free = 0;

    for (int d = 1; d <= k; d++) {
        for (int i = 1; i <= n[d]; i++) {
            int u = off[d] + i;

            if (root[u]) {
                int need = f[u];

                if (free < need) {
                    ans += (need - free);
                    free = 0;
                } else {
                    free -= need;
                }
            }
        }

        for (int i = 1; i <= n[d]; i++) {
            int u = off[d] + i;
            if (g[u].empty()) free++;
        }
    }

    cout << ans << endl;
}