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#include <bits/stdc++.h>
using namespace std;

int main(){
	ios_base::sync_with_stdio(false), cin.tie(nullptr);
	int K;
	cin >> K;
	vector<vector<int> > meetings(K);
	for(int i = 0; i < K; i++){
		int N;
		cin >> N;
		meetings[i].resize(N, -1);
		if(i > 0){
			for(int& x : meetings[i]){
				cin >> x; x--;
			}
		}
	}
	vector<vector<int> > has_children(K);
	vector<vector<int> > start_day(K);
	for(int day = 0; day < K; day++){
		has_children[day].resize(meetings[day].size(), 0);
		start_day[day].resize(meetings[day].size());
		for(int i = 0; i < (int)meetings[day].size(); i++){
			if(meetings[day][i] >= 0){
				has_children[day-1][meetings[day][i]] = 1;
				start_day[day][i] = start_day[day-1][meetings[day][i]];
			} else {
				start_day[day][i] = day;
			}
		}
	}
	vector<pair<int,int>> intervals;
	for(int day = 0; day < K; day++){
		for(int i = 0; i < (int)meetings[day].size(); i++){
			if(!has_children[day][i]){
				intervals.push_back({start_day[day][i], day});
			}
		}
	}
	vector<int> deltas(K+1);
	for(auto [x, y] : intervals){
		deltas[x]++;
		deltas[y+1]--;
	}
	int ans = 0;
	int cur = 0;
	for(int x : deltas){
		cur += x;
		ans = max(ans, cur);
	}
	cout << ans << '\n';
}