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#include <bits/stdc++.h>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int k, n;
    cin >> k >> n;

    vector<vector<pair<pair<int, int>, vector<int>>>> meetings(k);

    for (int i = 0; i < n; ++i)
    {
        meetings[0].emplace_back(make_pair(0, 0), vector<int>());
    }

    for (int i = 1; i < k; ++i)
    {
        cin >> n;

        for (int j = 0; j < n; ++j)
        {
            int a;
            cin >> a;

            meetings[i].emplace_back(make_pair(a, 0), vector<int>());

            if (a != 0)
            {
                meetings[i - 1][a - 1].second.push_back(j);
            }
        }
    }

    int answer = 0;
    int left = 0;

    for (int i = k - 1; i >= 0; --i)
    {
        for (auto &[p, children] : meetings[i])
        {
            for (int child : children)
            {
                p.second += meetings[i + 1][child].first.second;
            }
            if (p.second == 0)
            {
                if (left) --left;
                else ++answer;
                ++p.second;
            }
        }
        for (auto &[p, children] : meetings[i])
        {
            if (p.first == 0) left += p.second;
        }
    }

    cout << answer << '\n';
}