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

typedef long long LL;

struct Meeting {
	LL par = -1;
	LL att_cnt = 0;
};

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

	int n;
	cin >> n;

	vector<vector<Meeting>> meetings(n);

	for (int i = 0; i < n; ++i) {
		int m;
		cin >> m;
		if (i == 0) {
			meetings[i] = vector<Meeting>(m, {-1, 0});
		} else {
			meetings[i].resize(m);
			for (int j = 0; j < m; ++j) {
				int par;
				cin >> par;
				--par;
				meetings[i][j] = {par, 0};
			}
		}
	}

	LL used = 0;
	LL left = 0;

	for (int i = n-1; i >= 0; --i) {
		for (auto& x : meetings[i]) {
			if (x.att_cnt == 0) {
				if (left == 0) {
					++used;
				} else {
					--left;
				}
				x.att_cnt = 1;
			}
		}
		for (auto& x : meetings[i]) {
			if (x.par == -1) {
				left += x.att_cnt;
			} else {
				meetings[i-1][x.par].att_cnt += x.att_cnt;
			}
		}
	}

	cout << used << '\n';

	return 0;
}