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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

int M = 500'010;
vector<vector<int>> g(M);
vector<int> up(M), dp(M), day(M); 

void dfs(int v) {
	if(g[v].size()==0) dp[v] = 1;
	for(auto u : g[v]) {
		dfs(u);
		dp[v] += dp[u];
	}
}

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

	int d, n;
	cin >> d >> n;
	int nxt = 1;
	for(int i=1; i<d; ++i) {
		int l; cin >> l;
		for(int j=0; j<l; ++j) {
			day[nxt + n + j] = i;
			int x; cin >> x;
			if(x) {
				--x;
				g[nxt+x].push_back(nxt + n + j);
				up[nxt+n+j]++;
			}
		}
		nxt += n;
		n = l;
	}
	vector<vector<int>> roots(d);
	vector<vector<int>> leaves(d);
	nxt += n;
	for(int i=1; i<nxt; ++i) {
		if(g[i].size()==0) {
			leaves[day[i]].push_back(i);
		}
		if(up[i]==0) {
			roots[day[i]].push_back(i);
			dfs(i);
		}
	}
	int free = 0;
	int res = 0;
	auto rekrutuj = [&]() {
		if(free > 0) free--;
		else res++;
	};
	auto zwolnij = [&]() {
		free++;
	};
	for(int i=0; i<d; ++i) {
		for(auto x : roots[i]) {
			for(int j=0; j<dp[x]; ++j) rekrutuj();
		}
		for(auto x : leaves[i]) zwolnij();
	}
	cout << res << "\n";

	return 0;
}