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#include <bits/stdc++.h>

using namespace std;

using ll = long long;

constexpr int N = 5e5 + 5;

vector<vector<int>> v;
vector<int> d[N], f, base;
int n, s, x, ans = 0, depth[N], c;

int dfs(int v) {
    if(d[v].empty()) {
        f[depth[v] + 1]++;
        return 1;
    } 
    int sum = 0;
    for(const int& ch : d[v]) sum += dfs(ch);
    return sum;
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> n >> s;
    v.resize(n), base.resize(n, 0), f.resize(n + 2, 0), v[0].resize(s, 0);
    for(int i = 0; i < s; ++i) depth[i] = 0;
    for(int i = 1; i < n; ++i) {
        base[i] = base[i - 1] + v[i - 1].size();
        cin >> s;
        v[i].resize(s);
        for(int j = 0; j < s; ++j) {
            cin >> v[i][j];
            depth[base[i] + j] = i;
            if(v[i][j]) d[base[i - 1] + v[i][j] - 1].push_back(base[i] + j);
        }
    }
    for(int i = 0; i < n; ++i) {
        c = 0;
        for(int j = 0; j < v[i].size(); ++j) {
            if(!v[i][j]) c += dfs(base[i] + j);
        }
        ans += max(0, c - f[i]);
        f[i + 1] += f[i] - min(f[i], c);
    }
    cout << ans << '\n';
}