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// Author: Bartek Knapik

#include<cstdio>
#include<vector>

const int MAXN = 1000000+9;

using namespace std;

struct Meeting
{
    bool is_first;
    bool is_last;
    bool is_checked;
    vector<int> follow_ups;
    long long n_participants;
    
    void start(bool is_first)
    {
        this->is_first = is_first;
        is_last = true;
        is_checked = false;
        follow_ups.clear();
        n_participants = -1;
    }
    
    void push(int id)
    {
        follow_ups.push_back(id);
        is_last = false;
    }
};

int k;
int ns[MAXN];
Meeting meetings[MAXN];
vector<int> q;

void dfs(int id)
{
    q.clear();
    q.push_back(id);

    while (q.size())
    {
        int cur = q[q.size() - 1];
        if (meetings[cur].is_last)
        {
            meetings[cur].n_participants = 1LL;
            q.pop_back();
        }
        else if (meetings[cur].is_checked)
        {
            meetings[cur].n_participants = 0LL;
            for (int i = 0; i < meetings[cur].follow_ups.size(); ++i)
                meetings[cur].n_participants += meetings[meetings[cur].follow_ups[i]].n_participants;
            q.pop_back();
        }
        else
        {
            for (int i = 0; i < meetings[cur].follow_ups.size(); ++i)
                q.push_back(meetings[cur].follow_ups[i]);
            meetings[cur].is_checked = true;
        }
    }
}

int main()
{
    int pos, a, prev_start, n_meetings;
    
    pos = 0;
    prev_start = 0;
    
    scanf("%d%d", &k, &ns[0]);
    
    for (int i = 0; i < ns[0]; ++i)
    {
        meetings[pos].start(true);
        pos++;
    }
    
    for (int i = 1; i < k; ++i)
    {
        scanf("%d", &ns[i]);
        for (int j = 0; j < ns[i]; ++j)
        {
            scanf("%d", &a);
            if (a)
            {
                meetings[pos].start(false);
                int parent_id = prev_start + a - 1;
                meetings[parent_id].push(pos);
            }
            else
                meetings[pos].start(true);
            pos++;
        }
        prev_start += ns[i-1];
    }

    for (int i = 0; i < pos; ++i)
        if (meetings[i].is_first)
            dfs(i);

    long long needed, released, available;
    long long most_needed;
    pos = 0;
    most_needed = available = 0LL;
    for (int i = 0; i < k; ++i)
    {
        needed = released = 0LL;
        for (int j = 0; j < ns[i]; ++j)
        {
            if (meetings[pos].is_first)
                needed += meetings[pos].n_participants;
            if (meetings[pos].is_last)
                released++;
            pos++;
        }
        if (available < needed)
        {
            most_needed += needed - available;
            available = 0;
        }
        else
            available -= needed;
        available += released;
    }
    printf("%lld\n", most_needed);
    return 0;
}