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#include <iostream>
#include <vector>

/*

4 3
3 1 1 1
4 0 0 2 0
2 3 3

2 1
2 0 0


*/

struct node_t
{
    std::vector<int> children;
    int num_workers_needed = 0;
};

std::vector<std::vector<node_t>> g;

int use_workers(int level, int index)
{
	node_t& node = g[level][index];
    if (node.num_workers_needed == 0)
    {
        if (node.children.empty())
		    ++node.num_workers_needed;
	    else for (int child_index : node.children)
            node.num_workers_needed += use_workers(level + 1, child_index);
    }
    return node.num_workers_needed;
}

int main()
{
    int k, n1;
    std::cin >> k >> n1;
    g.resize(k);
    g[0].resize(n1);
    for (int i = 1; i < k; ++i)
    {
    	int ni;
        std::cin >> ni;
		g[i].resize(ni);
		for (int j = 0; j < ni; ++j)
        {
            int parent;
			std::cin >> parent;
            if (parent)
            {
                --parent;
                g[i-1][parent].children.push_back(j);
            }
        }
	}
    int max_workers_needed = 0;
	for (int i = 0; i < k; ++i)
    {
		int num_workers_needed_on_day = 0;
        for (int j = 0; j < g[i].size(); ++j)
            num_workers_needed_on_day += use_workers(i, j);
        if (max_workers_needed < num_workers_needed_on_day)
			max_workers_needed = num_workers_needed_on_day;
    }
    std::cout << max_workers_needed;
    return 0;
}