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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
typedef long long LL;
typedef vector<LL> VI;

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

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

	VI dayStart(k + 1, 0);
	VI dayCount(k + 1, 0);

	dayCount[1] = n1;
	dayStart[1] = 0;

	int total = n1;
	vector<VI> parentLocal(k + 1);
	parentLocal[1] = VI(n1, 0);

	for (int day = 2; day <= k; ++day)
	{
		int ni = 0;
		cin >> ni;
		dayCount[day] = ni;
		parentLocal[day].resize(ni);

		for (int j = 0; j < ni; ++j) cin >> parentLocal[day][j];
		total += ni;
	}

	for (int day = 2; day <= k; ++day) dayStart[day] = dayStart[day - 1] + dayCount[day - 1];
	VI parent(total, -1);

	for (int j = 0; j < dayCount[1]; ++j) parent[dayStart[1] + j] = -1;
	for (int day = 2; day <= k; ++day)
	{
		int prevStart = dayStart[day - 1];
		int curStart = dayStart[day];

		for (int j = 0; j < dayCount[day]; ++j)
		{
			int a = parentLocal[day][j];
			if (a==0) parent[curStart + j] = -1;
			else parent[curStart + j] = prevStart + (a - 1);
		}
	}

	//Bottom-up

	VI childSum(total, 0);
	VI f(total, 0);
	LL answer = 0;

	for (int day = k; day >= 1; --day)
	{
		int start = dayStart[day];
		int cnt = dayCount[day];

		LL daySum = 0LL;
		for (int j = 0; j < cnt; ++j)
		{
			int v = start + j;
			f[v] = childSum[v] == 0 ? 1LL : childSum[v];
			daySum += f[v];
		}
		answer = max(answer, daySum);

		for (int j= 0; j < cnt; ++j)
		{
			int v = start + j;
			int p = parent[v];
			if (p != -1) childSum[p] += f[v];
		}
	}

	cout << answer << endl;
	return 0;
}